Where to start

A good first step is to test your site using tools like Google PageSpeed Insights. These tools help identify specific issues and offer actionable suggestions. You can use your Jetpack Boost score as a reference, but it’s more important to focus on how the site feels to visitors and to address the real bottlenecks these tools highlight.

Optimize theme and plugin setup

Some themes and plugins add extra code to every page—even when it’s not needed. A lightweight setup can make a big difference.

• Use a fast, well-coded theme. Themes vary widely in performance. If your current theme loads slowly, try switching temporarily to a default theme like Twenty Twenty-Five and comparing your PageSpeed score and visual loading time.
• Remove unused plugins and themes. If you’re not using it, it’s best to delete it. This helps reduce CSS and JavaScript bloat.
• Turn off Jetpack modules you don’t need. From Jetpack → Settings, disable features not essential to your site.

Cut down on third-party scripts

Scripts from external sources—like analytics, ad networks, social feeds, or marketing tools—can delay page rendering.

• Audit what’s loading. Use tools like PageSpeed or your browser’s DevTools to spot third-party scripts that might slow things down. In Chrome: right-click the page → Inspect → Network tab → refresh. Look for items loading from other sites (like ads or fonts). If something looks unfamiliar or unnecessary, it may be worth disabling a plugin or checking with your theme or host for advice
• Limit embeds and popups. Things like videos, social feeds, or popups often load extra scripts that can slow down your site. Only use what’s really needed, and avoid adding too many at once.

Use a caching plugin (if needed)

Jetpack Boost includes basic page caching, and some hosts provide their own. If you’re not using Boost, or your host doesn’t cache pages automatically and if you are looking for more advanced caching options, you can try WP Super Cache.

Optimize your images manually

Jetpack Boost’s Image CDN resizes and compresses images automatically. But if you’re not using it—or want even more control—you can:

• Resize images before uploading them.
• Use tools like TinyPNG or ImageOptim.
• Choose the right format (JPEG for photos, WebP if supported).
• Replace oversized or full-width images when not necessary.

You can use Jetpack Boost’s Image Size Analyzer to help identify images that can benefit from further optimization.

Use a CDN for static files

If you’re not using Jetpack Site Accelerator or Boost’s Image CDN, consider enabling them or using a service that provides this service. A CDN delivers your site’s static content (images, scripts, stylesheets) from servers closer to your visitors, reducing load time.

Reduce layout shift

If your page moves around while loading, your Cumulative Layout Shift (CLS) score will suffer. Here’s how to fix that:

• Avoid inserting content above existing content after page load.
• Use themes that load in a stable, predictable way.

Offload resource-heavy features

Features like search or related posts can slow down your site if handled on your own server. Jetpack offers cloud-powered options for both:

• Jetpack Search replaces WordPress’s built-in search with fast, scalable results.
• Related Posts can be served from Jetpack’s servers instead of being calculated on the fly.

Clean up your database

Old revisions, spam comments, and transients can slow your site down. You can use a plugin from the WordPress.org Plugin Directory to tidy up. These plugins typically offer one-click cleanup tools, and they explain what each item does before deleting anything. Be sure to back up your site first.

Check your server

A slow server can limit everything else you’ve optimized. If PageSpeed says your server is slow (look for ‘Reduce initial server response time’), talk to your hosting provider. Some may offer better performance plans or built-in caching.

If performance doesn’t improve, consider switching to a host optimized for WordPress.

Need help?

Jetpack Support is here for Boost-specific questions. While we can’t offer hands-on help with broader performance tuning, this guide is here to help you take the next steps and every improvement adds up.

VideoPress is a powerful video hosting and streaming service built for WordPress, making it a strong choice for adding high-quality video content to your Learning Management System (LMS) site. While the level of integration depends on the specific LMS plugin, many support basic embedding of VideoPress videos. Below, you’ll find an example using Sensei LMS, which offers built-in support for VideoPress, followed by a general overview of other commonly used LMS plugins.

Sensei LMS

Sensei LMS is developed by us, Automattic, the same company behind WordPress, Jetpack, and VideoPress, which ensures seamless integration, consistent design standards, and a cohesive user experience.

The benefits of using VideoPress with Sensei LMS

• Native Integration with VideoPress: Sensei LMS offers built-in support for VideoPress, allowing you to effortlessly embed videos into your courses. This integration ensures high-quality video playback and adaptive streaming for your students. ​
• Interactive Video Capabilities: Enhance your lessons with interactive videos by adding breakpoints that display quizzes, prompts, or additional content at specific times during video playback. This feature increases student engagement and retention.
• Content Protection: With VideoPress, you can protect your video content, ensuring that only enrolled students have access. This feature helps maintain the exclusivity and value of your course materials.
• Video Progression Requirements: Ensure students watch videos or interact with specific breakpoints before progressing through lessons.

How to use VideoPress with Sensei LMS

1. Upload your video to VideoPress: Upload your course videos using any of the supported methods.
   • For details, see how to upload videos to VideoPress.
2. Add the Video in Your Lesson:
   • In the WordPress editor, add a new block in your Sensei lesson.​
   • Select the VideoPress block.​
   • Choose the video you uploaded to VideoPress.​
3. Add Interactivity (Optional):
   • Transform the video block into an Interactive Video Block.
   • Add breakpoints to include quizzes or prompts during video playback.
     

Other LMS Plugins

There are many popular LMS plugins built for WordPress. While none are currently known to offer the same level of integration with VideoPress as Sensei LMS, several support basic embedding of VideoPress videos. Depending on the plugin, you may be able to add VideoPress content using a block, shortcode, or embed link — though features like role-based access or lesson gating may not be supported.

If you plan to use VideoPress with a third-party LMS and want to enable advanced features like access control or lesson progression, we recommend reaching out to the plugin’s support team to confirm compatibility and best practices.

Below are some examples of widely used WordPress LMS plugins that support embedding of VideoPress videos:

• LearnDash
• LifterLMS
• Tutor LMS
• MasterStudy LMS
• Masteriyo
• LearnPress

Note: Our support scope is limited when it comes to integration with third-party LMS platforms. For specific integration details or advanced feature support, we recommend reaching out to the LMS plugin’s support team directly.

Site Builders: Elementor and Divi

While not LMSs, popular site builders like Elementor and Divi have added support for the VideoPress block. This may be useful if you’re creating custom LMS-like content pages and want reliable video playback.

The tables below provide a breakdown, so you can make informed decisions about your site and data.

Data retention for current plan offerings

The Activity Log’s data retention periods depend on the activity and the site’s plan. This table covers the retention periods for the plans currently available on our plans page.

Data Retention for Previous Plan Offerings

The Activity Log’s data retention periods depend on the activity and the site’s plan. This table covers the retention periods for the plans you may currently use but are no longer available for purchase via Jetpack.com (legacy plans).

^* Activity present in a site’s activity log but not currently shown to the site owner in the UI.

** Subject to your usage and storage limit. Learn more about Jetpack VaultPress Backup storage and retention.

NOTE: at the end of any retention periods outlined above, activity data is moved to long-term storage and is retained indefinitely. Once in long-term storage, activity data will no longer be visible in a site’s activity log.

Privacy Information

The Activity Log is activated by default. There is currently no way to deactivate this feature.

With Jetpack installed and connected, the Stats column appears by default in the list of posts or pages in WP Admin. Each row includes an eye icon with a number next to it showing total views in the past 30 days.

This makes it easy to review performance at a glance without opening the full Jetpack Stats panel.

Accessing more Stats

To view detailed statistics for an individual post or page, click the eye icon in the Stats column next to that post or page. This will open the Jetpack Stats summary for the selected content.

In the detailed view, you’ll see:

• Total views, likes, and comments
• Traffic charts by day, week, month, or year
• All-time engagement stats
• If available, campaign UTM data for incoming traffic

Adjusting the display

While the Stats column is enabled by default, you can control if columns appear in the post and pages lists:

1. Click Screen Options at the top right of the Posts or Pages screen.
2. In the Columns section, check or uncheck Stats as needed.
3. Click Apply to update the view.

Why your site speed score matters

A faster site isn’t just a technical goal—it makes your content easier to reach, your visitors more likely to stay, and your site  feel smoother all around.

Jetpack Boost provides a performance score based on Google PageSpeed, so you can see how your site performs and where there’s room to grow. You’ll see:

• A numeric score and letter grade for Mobile and Desktop
• A clear visual meter showing your performance level
• A history of your scores over time (available with a paid plan)

Mobile scores are often lower than desktop scores—don’t worry, that’s expected. Boost helps you improve both.

How Jetpack Boost helps speed up your site

Jetpack Boost focuses on front-end performance—what your visitors interact with. Boost helps pages load faster by optimizing CSS, JavaScript, images, and caching.

You can turn each feature on or off from WP Admin → Jetpack → Boost.

Optimize CSS loading

When a browser loads your site, it first looks at the design instructions provided by a site’s CSS (Cascading Style Sheets). These instructions define presentational details: colors, font sizes, etc. If the browser has to interpret all of these instructions before showing the page, it can slow things down.

Jetpack Boost solves this by identifying the Critical CSS—the instructions needed to load the visible part of the page—and puts that first. This means your site starts displaying sooner, even before everything else loads.

This can improve scores like First Contentful Paint and Largest Contentful Paint, which measure how quickly your content becomes visible.

• With the free version, you will need to regenerate Critical CSS manually when you make major changes.
• With a paid plan, Boost automatically updates your Critical CSS in the background when needed.

Cache site pages

When someone visits your site, WordPress builds the page from scratch. That takes time.

Page caching saves a ready-to-go version of your pages so visitors don’t have to wait. Caching can help reduce server response time and speed up repeated visits. It’s like handing out a finished copy instead of writing it again every time.

• Enable Cache Site Pages in Boost to load your content faster.
• If this option isn’t visible, it may be handled already by your hosting provider.

Defer non-essential JavaScript

Some scripts on your site—like popups, sharing buttons, or animations—aren’t needed immediately when the page loads.

Boost can defer these scripts so they load after your main content, helping the page load faster. This can improve render times and help with PageSpeed warnings like “Reduce JavaScript execution time.”

• Turn on Defer Non-Essential JavaScript to prioritize your main content.
• If something doesn’t work as expected, you may need to exclude a specific script or turn this off temporarily.

Concatenate JavaScript and CSS

Every CSS or JavaScript file your site loads is an extra request to your server—and each request slows down overall page loading.

Concatenation combines multiple files into one, which means fewer requests and faster loading. This helps reduce Total Blocking Time by making your site easier for the browser to process.

• Turn on Concatenate JS and Concatenate CSS to streamline how your site loads assets.
• If any designs or features break, you may need to exclude specific files. Learn how.

Use the Image CDN

Images are often the biggest contributor to slow sites. Boost’s Image CDN automatically resizes, compresses, and serves your images from high-speed servers around the world. This improves the Cumulative Layout Shift and overall page load time, especially on mobile.

• Turn on Image CDN to optimize all images across your site automatically.
• With a paid plan, you can adjust image quality and enable Auto-Resize Lazy Images, which helps images load only when needed—and at the right size.

Identify large images

Even with a CDN, oversized images can still lower your site speed. Keeping image dimensions appropriate helps both speed and layout stability. Boost includes tools to help you spot the worst offenders.

• Use the Image Performance Guide and Image Size Analyzer to detect images that are too large for their space.
• Replace or resize them using an image editor or online compression tool.

If your speed score is still low

Jetpack Boost takes care of many technical optimizations, but it can’t fix every issue on its own. If you’ve enabled all Boost features and your score still isn’t where you’d like, other factors may be affecting your site’s performance. Here are some common next steps:

• Remove unused plugins or scripts – Extra code can slow down your site.
• Use a lightweight theme – Some themes are better optimized than others.
• Test with Google PageSpeed Insights – See what specific issues are being flagged.
• Talk to your hosting provider – A slow server (high TTFB) may need an upgrade or tuning.

Boost works best when paired with a clean setup and fast hosting. Think of it as part of the solution, not the whole package.

What Jetpack Boost helps with

Jetpack Boost is designed to improve how your site loads for visitors. It focuses on front-end performance and makes quick, impactful changes that can raise your speed scores. Specifically, Boost helps with:

• Faster delivery of CSS, JavaScript, and images
• Improvements to key Web Vitals:
  • FCP (First Contentful Paint): When something first appears on screen
  • LCP (Largest Contentful Paint): When the main content finishes loading
  • CLS (Cumulative Layout Shift): How stable the layout is as the page loads

What Jetpack Boost doesn’t cover

While Boost helps with many common performance issues, it doesn’t handle everything. It does not address:

• Server or hosting-related slowness (like TTFB or slow response times)
• Unused code, plugins, or third-party scripts
• Guaranteeing a perfect score in Google PageSpeed or Lighthouse

If your speed score is still lower than expected after enabling all Boost features, other factors—such as your theme, plugin setup, or hosting environment—may be involved.

Want to go further?

Our Advanced Site Speed Optimization guide includes practical steps for deeper testing, cleanup, and improvements beyond what Boost covers. It’s a great next step if you’re ready to fine-tune your site even more.

Jetpack Support is here to help with Boost-specific features, but general performance tuning is outside our scope.

Still need help?

If Boost isn’t working as expected or you’re unsure whether a feature is active, reach out to Jetpack Support, and we’ll be glad to help.

Requirements

AI-powered alt text and caption generation requires a website connected to Jetpack, using the block editor with Jetpack Blocks activated. For more details, check the Requirements.

The AI-powered alt text and caption generation only works for images in these formats: JPEG, PNG, WEBP, GIF.

Cost and Usage Limitations

Each AI-generated alt text or a caption is counted as one AI request. You are charged 1 request for each successful generation, whether you keep the result or not.

Jetpack AI offers you 20 free requests to get started. For more information about upgrading, please refer to our detailed Usage limitations and upgrades guide.

Use AI to Generate Alt Text and Captions

Jetpack AI Assistant can automatically generate descriptive alt texts and captions for your images. This feature is integrated directly into the Image block and can be accessed via the block toolbar.

Here is how:

1. Select the Image block in the editor.
2. Click the AI Assistant Sparkles icon in the block toolbar.
3. Choose one or both of the options:
   • Generate alt text – AI will analyze the image and generate an alternative text. It will appear in the Alternative Text field in the sidebar Block settings.
   • Generate caption – AI will analyze the image and add a caption.
4. The generated text can be edited as needed before publishing your content.

Why Alt Text Matters

Alt text improves accessibility, SEO, and user experience.

• Accessibility: Screen readers use alt text to describe images to visually impaired users. This helps make websites more inclusive.
• SEO: Search engines rely on alt text to understand image content. Well-written alt text can improve rankings and helps images appear in search results.
• User experience: If an image doesn’t load, alt text provides context so users still understand the content.
• Compliance: Many accessibility guidelines, like WCAG, require alt text for images.

Requirements

Jetpack Account Protection requires either the Jetpack plugin (version 14.5 or higher) or the Jetpack Protect plugin (version 4.1 or higher) along with the site connection. If you have both the Jetpack and Jetpack Protect plugins, you must upgrade them to at least versions 14.5 and 4.1, respectively.

This feature is activated by default, is free to use, and does not require a Jetpack plan.

How Account Protection works

Manage Account Protection activation

Account Protection is activated by default. Here is how you can manage the activation:

• If you have the Jetpack plugin active:
  1. Navigate to Jetpack → Settings.
  2. Locate the Account Protection section in the Security tab (the default tab).
  3. Toggle Protect your site with advanced password detection and profile management protection.
• If you have the Jetpack Protect plugin active:
  1. Navigate to Jetpack → Protect.
  2. Open to the Settings tab.
  3. Toggle Account Protection.

If the setting is disabled and activation is not possible, please check the Unsupported environments section.

Add extra security checks when saving a password

Jetpack Account Protection performs additional security checks whenever a user sets or updates their password.

Passwords are evaluated against the following additional criteria:

• Must not contain a backslash character.
• Must be between 6 and 150 characters.
• Must not appear in known data breaches. Attackers frequently use passwords leaked in public breaches to gain unauthorized access.

When you update your password in WP Admin → Users → Profile, we perform additional checks to ensure security:

• The password must not match any part of your user data (e.g., display name, username, first or last name, email address, or nickname). Using a password similar to your personal details makes guessing easier for attackers.
• The password must not be identical to a previously used password. Reusing old passwords increases security risks.

Prevent unverified logins from using leaked passwords

Account Protection adds an extra layer of security to the login process.

We automatically check passwords against a database of known breaches for users with the role of Author or higher. If a compromised password is detected, an additional verification step is required. No configuration is needed—this happens automatically. Here’s how it works:

1. A WP Admin user attempts to log in, and Jetpack detects that their password has been compromised.
2. A 6-digit verification code is sent to the user’s email address.
3. The user sees a Verify Your Identity form, where they must enter the verification code. They can also request resending a new code if needed.
4. Once the code is submitted, the user is prompted to either Create a New Password (recommended) or Proceed Without Updating.

Recover your account in case of issues with the verification code delivery

If you don’t receive your verification code, here’s what you can do. We send the code to the email address associated with your WP Admin user profile.

If you no longer have access to that mailbox:

1. Contact support, and we will deactivate the Account Protection module for you.
2. After regaining access to your account, access your user profile at https://yourjetpack.blog/wp-admin/profile.php where yourjetpack.blog is your site’s domain. Once there, you will need to:
   • Update the Email field with your current email address.
   • Update the Password field with a strong, uncompromised password.

If you have access to the mailbox:

• Try to resend the code. You can resend it three times per session. You should be able to make subsequent attempts every 15 minutes.
• If you still haven’t received the code, you can reset your current password. Once you update your password to a strong, uncompromised one, you will no longer be blocked by our Account Protection.

Unsupported environments

The Jetpack Account Protection feature can be disabled by your hosting provider to avoid conflicts with platform-specific security solutions. Your site administrator can also manually disable it in the wp-config.php file:

define( 'DISABLE_JETPACK_ACCOUNT_PROTECTION', true );

In such cases, you will not be able to activate Account Protection. Instead, you will see a notice stating that this feature is disabled by your site administrator or hosting provider.

Risks of using a weak password

As a WordPress Administrator, your password is the first line of defense against unauthorized access. A weak password can put your entire site at risk. Here’s why strong password security is essential:

• Easy Target for Attackers: Weak passwords make your site vulnerable to brute-force attacks, where hackers systematically guess passwords to gain access.
• Higher Risk of Credential Theft: If you reuse passwords across multiple sites, a breach on another platform could expose your WP Admin account to attackers.
• Loss of Administrative Control: Attackers can make unauthorized changes, delete content, or insert malicious code.
• User and Data Breach Risks: Attackers with admin access can steal user information, including emails and personal details, putting your visitors at risk.
• SEO and Reputation Damage: If your site is hacked, search engines may flag it as unsafe, leading to lower search rankings and loss of visitor trust.
• Time-Consuming Recovery Process: Regaining control over a hacked site requires resetting credentials, restoring backups, and securing vulnerabilities—all of which take time and effort.
• Potential Legal and Compliance Issues: Depending on your industry, a security breach could result in legal consequences, including fines for failing to protect user data.
• Financial Losses: A compromised site can lead to lost revenue, particularly for WooCommerce businesses, membership sites, or any site that relies on visitor engagement.

Privacy

Account Protection is activated by default. Check Manage the activation of Account Protection to learn how to deactivate it.

Jetpack Boost (v3.9.0 and later) optimizes WordPress performance by concatenating and minifying CSS and JavaScript files, delivering them directly from your web server for faster load times.

When direct delivery isn’t possible, a fallback system using PHP ensures content is still accessible while optimization efforts continue.

How to check which delivery method is in use

To determine which delivery method your site is currently using, follow the steps:

1. Open a page on your website in a browser.
2. View the page source (right-click → View page source).
3. Look for CSS or JavaScript file URLs:
   • If they are loaded from /wp-content/boost-cache/static/, congratulations! Your site is already set up for direct delivery of these files.
   • If they are served from /_jb_static/, it means WordPress is handling the delivery, which may slow down requests slightly as PHP processes these files. While concatenating multiple files into one is generally beneficial, you may want to explore why direct delivery isn’t functioning on your website.

Custom permalinks and file regeneration

Jetpack Boost relies on WordPress’s custom permalinks system to regenerate these concatenated files. If a file is missing, WordPress detects the issue, triggering a regeneration process in Jetpack Boost. The plugin periodically checks if WordPress detects missing files in the wp-content directory. If this check fails, files are served using the /_jb_static/ method via PHP.

Manual Testing

If your site is using /_jb_static/ to serve the concatenated files, you can perform a manual test by attempting to access a non-existent URL within the /wp-content directory. It should look like a file the plugin uses, such as /wp-content/boost-cache/static/1234.css. Look for a WordPress 404 error page. If, instead, you see a standard web server 404 error, this confirms there is an issue requiring resolution.

When does the automatic 404 test run?

The plugin performs a check when both Concatenate modules (JS and CSS) are disabled, and you enable one of them. It also runs once daily. This ensures ongoing monitoring of your site’s performance and file delivery mechanisms.

How to fix issues with wp-content

The issue likely stems from the underlying web server configurations tied to custom permalinks.

Fixing on Apache

On Apache servers, mod_rewrite rules manage this, which may be disabled in the wp-content directory. Check for a hidden .htaccess file within the wp-content directory. If present, look for the following directive:

RewriteEngine Off

Removing or commenting out this line may resolve the issue. However, if you’re unfamiliar with these configurations, contact your hosting provider for assistance.

If there is no .htaccess file in the wp-content directory, your hosting provider may have disabled the web server settings this plugin relies on. If that is the case, the plugin will fall back to using WordPress techniques to serve the concatenated CSS or JavaScript. It is slightly slower, but it is still beneficial to your website.

Fixing on non-Apache Servers

For non-Apache servers like Nginx, consult your server’s documentation or contact your hosting provider for guidance on modifying configuration files in /etc/nginx/.

Disable 404 testing

To disable the is_404() testing, define the constant JETPACK_BOOST_DISABLE_404_TESTER in an mu-plugin. Here is an example of how to set that constant.

<?php

if ( ! defined( 'JETPACK_BOOST_DISABLE_404_TESTER' ) ) {
    define( 'JETPACK_BOOST_DISABLE_404_TESTER', 1 )
}

After disabling the tester, and if you are certain that is_404() works in the wp-content directory, you can set the jetpack_boost_static_minification site option to 1. Set it to 0 to use the older way of serving these files.

Conclusion

It’s highly likely that the presence of a .htaccess file in your /wp-content directory is causing this issue. Addressing this configuration should resolve the problem and restore expected 404 test behavior. This adjustment will help ensure your files are being delivered as efficiently as possible, improving both performance and functionality.

Auto-sharing Custom Post Types with Jetpack Social

By default, Jetpack Social’s auto-sharing feature is only triggered when you publish a new blog post. If you want to enable auto-sharing for custom post types, follow one of the methods below.

Option 1: Adding support to an existing post type

To add Jetpack Social support to an existing post type, use the add_post_type_support() function. Follow these steps:

1. Open your functionality plugin:
   If you don’t have one, create a new plugin or add code to an existing one.
2. Add the following code:

add_action('init', 'my_custom_init');
function my_custom_init() {
    add_post_type_support('custom_post_type', 'publicize');
}

3. Replace the placeholder:
   Replace custom_post_type with your Custom Post Type slug.

Option 2: Adding support when registering the post type

To add Jetpack Social support while registering a new post type, follow these steps:

1. Open your functionality plugin or theme’s functions.php file
2. Add the following code:

function jetpackme_custom_post_type() {
    $args = array(
        'label' => __('Custom Post Type', 'text_domain'),
        'supports' => array('title', 'editor', 'publicize'),
        'public' => true
    );
    register_post_type('custom_post_type', $args);
}
add_action('init', 'jetpackme_custom_post_type', 0);

3. Replace the placeholder:
   Replace custom_post_type with your Custom Post Type slug.

Removing WooCommerce Products from Jetpack Social

By default, WooCommerce includes Jetpack Social support and your new products will be auto-shared to your social media accounts. You can disable this functionality by adding the following code snippet:

add_action('init', 'woo_publicize_remove');
function woo_publicize_remove() {
    remove_post_type_support('product', 'publicize');
}

Removing Jetpack Social Options from the New Post Screen

Jetpack Social includes filters that allow customization of its default behavior. You can make these customizations through additional plugins or by adding code to your theme’s functions.php file.

To remove Jetpack Social options from the New Post screen, follow the detailed instructions provided in the Jetpack Support documentation.

Please be aware that code snippets are provided as a courtesy and our support team is unable to offer assistance customizing them further.

Understanding the Page Cache in Jetpack Boost

Jetpack Boost’s Page Cache feature generates and stores static versions of dynamic WordPress pages. The URL of a page and the browser cookies of the visitor are what we use to identify a page.

A person who visits a page with no cookies in their browser is described as an “anonymous user” because they have no data to identify them. The cache file generated for them can potentially be used for many other visitors. To maximize speed, these cached pages are served before WordPress fully initializes, which means most WordPress functionalities are unavailable at this stage.

For developers who need to execute code early in the page-serving process, Jetpack Boost provides the Extra Code Loader. This tool enables the execution of custom code before two critical points in a WordPress request:

1. When a cached page is served.
2. When the output buffer is created to cache a new page.

This functionality allows developers to implement necessary operations or modifications even when working with cached pages, ensuring both speed and customization capabilities.

Customizing cache behavior with filters

To modify cache parameters, you can create a file named wp-content/boost-cache-extra.php. Jetpack Boost will load it and execute it like any other PHP script. The file must have an opening <?php tag.

This script will execute very early in the process of serving a page, and this means that most WordPress functionality will not be available. However, filters and actions can be used.

Important: Ensure the file contains valid PHP code to avoid issues that could disrupt your site. It’s highly recommended to test any changes on a staging environment before applying them live.

Available filters

Jetpack Boost provides several filters for cache customization:

• jetpack_boost_ignore_cookies: Accepts one parameter, an array of cookie names. These cookie names are ignored and removed from the list of cookies that go to identify a cache file. Regular expressions can be used in the cookie names. The default list of cookie names includes the Cloudflare cookies described here, a regular expression matching any cookie starting with sbsj_ and the tk_ai and tk_qs cookies. This means that a visitor with any of these cookies in their browser will see the cache file created for anonymous visitors to the site, instead of getting a custom cache file.
• jetpack_boost_ignore_get_parameters: Accepts one parameter, an array of GET parameter names. These parameters are ignored by the cache in the same way the filter above works. The default list of parameters includes some of the “utm_” parameters used for marketing purposes.
• jetpack_boost_cache_parameters: Accepts one parameter, an array. This is similar to the filters above, but it contains both the cookies and get information. It runs earlier in the request than the filters above, but it’s recommended to use the other filters instead of this one. The filters above use this one.
• jetpack_boost_cache_bypass_patterns: Accepts one parameter, an array of regular expressions. It allows the site owner to modify the list of patterns to match against URLs that bypass caching. These are the URLs listed in the Exceptions form of the settings page.
• jetpack_boost_cache_request_cacheable: Accepts one parameter, a boolean. Return true to make the current page cacheable.
• jetpack_boost_cache_accept_headers: Accepts one parameter, an array of accept headers that the plugin will not cache. The default list includes various JSON header types.

In the list of cookies used by Boost, the Jetpack Cookie Banner eucookielaw and personalized-ads-consent cookie values are set to 1 so visitors who click the Accept button on the cookie banner will all be served the same cache file (if all other cookies are the same), to improve the efficiency of the cache. The cookies themselves are not modified, and a new cache file will be created for visitors who click Accept on the cookie banner.

If your site has a cookie with a value that changes on every page load, but the value itself isn’t used by any PHP code, it may be stopping your site from caching effectively. Use the jetpack_boost_cache_parameters filter to modify the value so it’s a consistent value on every page load.

Why ignore certain cookies?

Cookies play a crucial role in identifying website visitors. When a user logs in, a cookie is placed on their browser, but cookies serve various tracking purposes beyond just modifying page content. For first-time visitors and bots who view an “anonymous” version of the website, a frequently used cached page is typically served, as these types of visitors often outnumber those who have interacted with the site. Once a cookie is set, a new cache file is created for the page, and subsequent visitors with that cookie will be served that specific cache file. This process is essential because the cookie’s presence identifies the visitor in some manner.

However, if JavaScript on the website sets a cookie that doesn’t influence the site’s appearance through PHP, it may be safe to disregard that cookie. It’s important to note that certain cookies, such as WordPress login cookies, cannot be ignored due to their critical functionality.

Examples of modifying cache behavior with filters

Ignore a cookie

To ignore a cookie, such as one set by a cookie banner, use the jetpack_boost_ignore_cookies filter. This example demonstrates how to ignore the cookie_banner_settings cookie in a hypothetical cookie banner plugin that uses it. Any code that relies on this cookie has to be in JavaScript, running in the browser. If PHP on the server used it, to decide whether to display the banner, or perform other functionality, the cookie cannot be ignored.

<?php
// Ignore the 'cookie_banner_settings' cookie.
function ignore_banner_cookie( $cookies ) {
        $cookies[] = 'cookie_banner_settings';

        return $cookies;
}
add_filter( 'jetpack_boost_ignore_cookies', 'add_test_cookie' );

This code ensures that the cookie_banner_settings cookie is ignored, allowing a single cache file to be served to anonymous visitors.

Ignore a GET parameter

To exclude a specific GET parameter like test from cache identification, use the jetpack_boost_ignore_get_parameters filter. This example ensures URLs with the ?test parameter serve the same cache file as the base URL:

<?php
// ignore the 'test' GET parameter in the URL.
function ignore_test_get( $get) {
        $get[] = "test";
        return $get;
}
add_filter( 'jetpack_boost_ignore_get_parameters', 'ignore_test_get' );

This code removes the test parameter from cache identification, ensuring pages like yourjetpack.blog/?test=123 serve the same cached file as yourjetpack.blog/.

Pages that will now share the same cache file:

• yourjetpack.blog/
• yourjetpack.blog/?test=1
• yourjetpack.blog/?test=testing
• yourjetpack.blog/?test=123

Fix a constantly changing cookie value

This is an example where a hypothetical page counter cookie is set to 1 in the cache parameters. We can only do this when JavaScript displays the counter, not PHP. This allows the WordPress page to be cached and used by more visitors, while the counter displays how many pages they have visited.

<?php
// Fix the "page_counter" cookie
function fix_page_counter( $parameters ) {
        if ( isset( $parameters['cookies']['page_counter'] ) ) {
                $parameters['cookies']['page_counter'] = 1;
        }

        return $parameters;
}
add_filter( 'jetpack_boost_cache_parameters', 'fix_page_counter' );

Customizing your cache behavior with Jetpack Boost’s filters allows you to optimize performance and ensure a seamless experience for your site visitors. By ignoring unnecessary cookies and GET parameters, you can serve more efficient cached pages and reduce server load.

Disable caching under particular conditions

If you would like a certain page on your site to be shown without caching, but only to particular visitors, you can use the jetpack_boost_cache_request_cacheable filter. In this example, any visitor using the IP address 192.168.1.1, and has the cookie “source=vip” will be able to access an uncached /about/ page.

<?php

function uncacheable_vips( $cacheable ) {
        if (
                isset( $_SERVER['REQUEST_URI'] ) && $_SERVER['REQUEST_URI'] === '/about/' &&
                isset( $_COOKIE['source'] ) && $_COOKIE['source'] === 'vip' &&
                isset( $_SERVER['REMOTE_ADDR'] ) && $_SERVER['REMOTE_ADDR'] === '192.168.1.1'
        ) {
                return false;
        } else {
                return true;
        }
}
add_filter( 'jetpack_boost_cache_request_cacheable', 'uncacheable_vips' );

Still need help?

Please contact support. We’re happy to advise.