=== Jetpack Boost - Website Speed, Performance and Critical CSS === Contributors: automattic, xwp, adnan007, bjorsch, danwalmsley, davidlonjon, dilirity, donncha, ebinnion, exelero, jeherve, jpolakovic, karthikbhatb, kraftbj, lsarsfield, luchad0res, pyronaur, rheinardkorf, scruffian, thingalon, dlocc Donate link: https://automattic.com Tags: performance, speed, web vitals, critical css, cache Requires at least: 7.0 Tested up to: 7.1 Requires PHP: 7.4 Stable tag: 4.7.1 License: GPLv2 or later License URI: http://www.gnu.org/licenses/gpl-2.0.html Speed up your WordPress site with one-click optimizations like Page Cache, Critical CSS, and Image CDN to improve Core Web Vitals. == Description == Speed up your WordPress site by optimizing page performance with Jetpack Boost. Easily activate one-click optimizations to boost your Core Web Vitals. Did you know that a faster website:- - Ranks higher on Google. - Improves bounce rate (people stay on your site for longer). - Increases your conversion rate. Increase your website performance and speed up your website with one-click optimizations that supercharge your WordPress site’s performance and improve core web vitals scores for better search engine listings. Improving Core Web Vitals helps you rank higher on Google. A faster website also improves your SEO, helps you reduce your bounce rate and increase your ecommerce conversion rate. - Largest Contentful Paint (LCP): Measures loading performance. Improve your LCP and improve your website loading speed. - Interaction to Next Paint (INP): Measures responsiveness. To improve user experience pages should have a low INP. - Cumulative Layout Shift (CLS): Measures visual stability. Lowering your CLS helps improve your user experience. ### Performance Modules Optimize your website with the same techniques used on the world's most successful websites. Each technique that is used to increase website performance is packaged up as a module that you can activate and try out. Currently, the plugin has 8 performance modules available: 1. *Optimize CSS Loading* generates Critical CSS for your homepage, posts and pages. This can allow your content to show up on the screen much faster, particularly for viewers using mobile devices. Read more about critical CSS generation at [web.dev](https://jetpack.com/redirect/?source=jetpack-boost-critical-css) 2. *Page Cache* speeds up your site by saving pages as static files. These files are quickly served to visitors, reducing load times and enhancing user experience. 3. *Defer Non-Essential JavaScript* moves some tasks to after the page loads, so that important visual information can be seen sooner and your website loads quicker. Read more about deferring JavaScript at [web.dev](https://jetpack.com/redirect/?source=jetpack-boost-defer-js) 4. *Image Guide* is a must-have feature for anyone who wants to optimize the images on their website. With this guide, you can ensure that the images on your site are the right size and dimensions, which is critical for improving user experience, page speed, and site ranking. Following the tips and best practices outlined in the guide, you can reduce image file sizes and speed up your site. Check out our [support page](https://jetpack.com/support/jetpack-boost/image-performance-guide/) to learn more about this feature and how it can help you achieve a faster and smoother website experience for your users. 5. *Image CDN* allows your site to serve automatically-resized images in modern web formats directly from Jetpack's worldwide Content Delivery Network. Read more about Image CDNs at [web.dev](https://web.dev/image-cdns/) 6. *Concatenate and Minify CSS and JS* combines and shrinks your JavaScript and CSS resources to reduce the number and size of requests to your server, ensuring your content loads faster. Read more about minifying files at [web.dev](https://web.dev/minify-css/) 7. *Optimize LCP Images* improves the Largest Contentful Paint (LCP) of your Cornerstone Pages by optimizing their key image, so your most important content shows up sooner. 8. *Prerender Cornerstone Pages* loads your Cornerstone Pages in the background before visitors click a link to them, so your most important pages appear almost instantly. Don’t want to have to manually generate your critical CSS each time you update your site? Let us do the heavy lifting for you with automated critical CSS – each time you update your site we will automatically regenerate your critical CSS and update your performance scores. Upgrading also gives you dedicated email support access. ### With 💚 by Jetpack This is just the start! We are working hard to bring more features and improvements to Jetpack Boost. Let us know your thoughts and ideas! We'd also like to give a special THANK YOU to the XWP team who provided help with initial research and scoping of the plugin and were engaged with our team throughout the project. == Frequently Asked Questions == = What does Jetpack Boost do to help speed up my WordPress site? = Jetpack Boost makes small changes to the way that data is sent from your WordPress site to your users’ browser, to enable the browser to display your site faster. Jetpack Boost includes a growing number of separate features which can be turned on individually to improve your site’s performance. These include: * **Optimize CSS Loading**: This feature determines the most important CSS that your site needs to display your site’s initial content as quickly as possible, and embeds it directly into your site header. * **Page Cache**: This feature stores your website's pages as static HTML files, bypassing the need for dynamic generation. This means visitors receive pages faster, reducing wait times and improving overall site performance. * **Defer Non-Essential JavaScript**: This feature forces all of the JavaScript which is not deemed essential to displaying your site to load after your site’s main content has been loaded. * **Image CDN**: This feature automatically resizes images to a more appropriate size for your visitors' screens, converts them to modern image formats, and serves them from Jetpack's worldwide network of servers. * **Concatenate JS**: This feature reduces the size of your JavaScript resources, and automatically combines them into fewer files, allowing your site to load faster with fewer requests. * **Concatenate CSS**: As with concatenating JavaScript, this feature shrinks your CSS files and allows them to load with fewer requests. = What speed improvements can I expect when using Jetpack Boost? = Website Performance is complicated and can be affected by a number of factors. As a result, it is difficult to accurately predict how much impact it will have on each site. Generally, the lower your speed score is to begin with, the more Jetpack Boost may impact your performance. We have seen user reports of up to 25 Speed Score points improvement simply by installing and using Jetpack Boost. However, as performance can be impacted by so many factors, it is also possible for Jetpack Boost to have a small negative performance impact in some rare cases. We recommend that you install Jetpack Boost, and try it for yourself. It includes a tool for measuring your Speed Score, to check what impact it has on your site. = Can I also defer non-essential CSS with Jetpack Boost? = Jetpack Boost automatically defers non-essential CSS when its “Optimize CSS Loading” feature is enabled and Critical CSS has been generated. The “Optimize CSS Loading” feature identifies the most important CSS rules your site needs to display your pages as quickly as possible (commonly called “Critical CSS”), and defers all other CSS rules from loading until your main content has loaded. = What are Web Vitals? = Web Vitals are the measurements that Google uses to better understand the user experience on a website. By improving Web Vitals scores you're also improving the user experience on your site. You can read more about Web Vitals on [web.dev](https://jetpack.com/redirect/?source=jetpack-boost-vitals) = How does Jetpack Boost plugin improve Core Web Vitals? = Each Core Web Vital relates to an aspect of how quickly your site can load and appear on new visitors’ screens. Jetpack Boost makes small changes to the way that data is sent from your WordPress site to your users’ browsers, to enable your content to load faster. As a result, it can improve your Core Web Vitals scores. For example, our “Optimize CSS Loading” feature ensures the most important CSS rules are sent to users’ browsers as early as possible, improving both First Contentful Paint (FCP) and Cumulative Layout Shift (CLS) scores. = Does this plugin require Jetpack? = Jetpack Boost is a part of the Jetpack brand, but it doesn’t require Jetpack plugin to run. This is a separate plugin from Jetpack and it will always remain that way. = Will this plugin be able to improve performance on any website? = This plugin includes a range of performance improvements, which can help almost any WordPress site perform better. However, if your site is already extremely well optimized, Jetpack Boost may not have much room to improve it. Jetpack Boost includes a tool for measuring your site’s Speed Score - we encourage users to try it out and see what impact it can have for them. = How do I know if it's working? = Every site is different and so performance benefits for each module may vary from site to site. That's why we recommend that you measure the performance improvements on your site by enabling the performance modules one by one. There are many tools out there that you can use for free to measure performance improvements: * [WebPageTest.org](https://jetpack.com/redirect/?source=jetpack-boost-webpagetest) * [web.dev/measure](https://jetpack.com/redirect/?source=jetpack-boost-measure) * [PageSpeed Insights](https://jetpack.com/redirect/?source=jetpack-boost-pagespeed) * [GTMetrix](https://jetpack.com/redirect/?source=jetpack-boost-gtmetrix) Google PageSpeed measurements are built-in the Jetpack Boost dashboard. = Is Speed Optimization with Jetpack Boost safe? = Yes, it’s safe to try Jetpack Boost on any WordPress site. Jetpack Boost does not alter your site’s content, it only modifies the way the content is sent to the user’s browser to allow it to display faster. As a result, all of Jetpack Boost’s features can safely be turned off in the event of an incompatibility with your other plugins. = How does Jetpack Boost compare with other speed optimization plugins? = Speed Optimization plugins for WordPress can be complicated and opaque for users. They often offer columns of checkboxes with little explanation, and don’t include tools to measure the impact of each change or choice users make. Jetpack Boost aims to be as easy to use as possible, and includes a Speed Score indicator to help users immediately measure the impact of their choices. = Does it work with static page cache? = Absolutely! If you have plugins like WP Super Cache or W3 Total Cache installed - Jetpack Boost is only going to help increase the performance benefits! Keep in mind that you need to wait for the cache to clear for Jetpack Boost improvements to show up. = Can Jetpack Boost make my website load faster if I have a large database? = Jetpack Boost does not include any optimizations that target large databases at this time. However, watch this space - we are always looking for new ways to help our users perform better. = Does Jetpack Boost help with image optimization? = Jetpack Boost's Image CDN feature automatically converts your images to more modern web formats, resulting in smaller image file sizes without a loss in quality. = Is Jetpack Boost compatible with other caching and speed optimization plugins? = With few exceptions, Jetpack Boost has no problems running alongside most caching and speed optimization plugins. As a guideline, we don’t recommend enabling the same feature in multiple optimization plugins. For example, if two plugins attempt to defer your non-essential JavaScripts, then they may end up conflicting with each other and cause display problems on your site. If you run into compatibility issues, please do let us know. You can drop us a line on [the Jetpack Boost Support Forums](https://wordpress.org/support/plugin/jetpack-boost/) at any time. == Installation == 1. Install Jetpack Boost via the plugin directory, and activate it. 2. Activate Jetpack Connection 3. Turn on performance modules one by one and observe how the performance score changes == Screenshots == 1. Jetpack Boost dashboard with performance scores and optimization modules. 2. Free Critical CSS generation in progress. 3. Automatic Critical CSS generation with the upgraded plan. 4. Historical performance tracking with the upgraded plan. == Changelog == ### 4.8.0-beta2 - 2026-09-29 #### Security - Critical CSS: Only enter generation mode while a front-end page renders, so a link carrying the generation parameter can no longer force an admin, REST or login-page request to render as a logged-out visitor. #### Added - Connection: Surface SSL certificate verification failures reported by WordPress.com as a connection error notice. - Critical CSS: Explain when pages could not be optimized because they are only shown to logged-in visitors. - Settings: Add an explanation of Critical CSS beside its title in the modern dashboard. #### Changed - Cornerstone Pages: Add a short description under the title on the settings page. - Cornerstone Pages: Show the section description in the collapsed Settings header. - Dashboard: Move the speed test to a "Run speed test" button in the modernized Overview header and add a page subtitle. - Dashboard: Replace the free-plan score history prompt in the modernized Overview with a one-line upgrade notice that expands to a preview of the chart. - Dashboard: Show a loader instead of the modernized Overview while onboarding redirects to Getting Started. - Dashboard: Show score gains as badges in the modern Overview, and explain a score that has not improved or has fallen. - Dashboard: Show the modernized dashboard by default. Add `add_filter( 'rsm_jetpack_ui_modernization_boost', '__return_false' );` to restore the previous dashboard. - Dashboard: Update the modernized Overview score card to show "Your site speed", an overall band, and its calculating and failure states inside the card. - Dashboard: Use the same light orange for "Could improve" days in the modernized Overview history chart as in the score card. - Hide the Boost sidebar item when Boost is not active. - History chart: Give the empty-day tooltip card its own rounded shadow. - My Jetpack: Answer module switch clicks immediately, and explain what happened when a change fails. - My Jetpack: Restyle dashboard notices to match the WordPress design system. - My Jetpack: Show a Features tab in place of the Products tab. - My Jetpack: Show the dashboard in the new rounded admin page frame. - My Jetpack: Show the Jetpack menu notification badge when a connection error is detected. - Overview: Open the points explanation when hovering the points badge. - Overview: Show empty days in the score history in the same details popover as recorded days. - Refer to Cornerstone Pages consistently, matching the support documentation. - Restyle error notices to match the WordPress design system. - Settings: Add a Clear cache button to Page Cache and show logging as a toggle with a link to the logs. - Settings: Group Image CDN controls and LCP optimization status in inset panels on the modern dashboard, and label the auto-resize toggle. - Settings: Keep focus on tooltip triggers when their tooltips open, announce the content to screen readers, and show a focus ring after clicking an info icon. - Settings: Organize modern settings into collapsible sections with descriptions and icons. - Settings: Show performance scores and optimization settings together on the modern dashboard. - Settings: Show upgrade notices without prices and add an explicit Generate step for manual Critical CSS in the modern dashboard. - Settings: Simplify modern settings descriptions and labels, and remove tips and priority support from the modern settings page. - Settings: Use a shared Except panel for JavaScript, CSS, and page cache exclusions in the modern dashboard. - Update package dependencies. #### Fixed - Activity Log: Honor the module setting, so the page can be turned off. - Activity Log: Stop the frame from flashing while loading and when switching admin pages. - Charts: Fix unreadable axis labels in forced-colors mode. - Charts: Restore keyboard focus after dismissing line chart tooltips. - Connection: Fix a stale connection error notice that could persist on healthy sites. - Connection: Let users without admin access reconnect their own broken account from the connection error notice. - Connection: Report a broken connection on My Jetpack's connection card instead of claiming everything looks good, and show a break only the connection owner can repair as a warning, not an error, to everyone else. - Critical CSS: Avoid duplicate status requests for CSS and LCP generation in the modern dashboard. - Critical CSS: Hide only the group of blocked pages you dismiss, instead of both. - Critical CSS: Match the recommendations page text size and colour to the modern dashboard. - Critical CSS: Show a focus ring around the manual regeneration info icon when it is reached with the keyboard. - Critical CSS: Stop generation from logging administrators out on sites whose login gate redirects without using WordPress. - Critical CSS: Stop local generation at login-protected pages to keep administrators logged in, and prevent automatic restarts after a failed run throughout the dashboard page session. - Dashboard: Avoid redundant requests when toggling optimization modules. - Dashboard: Fix the modernized onboarding loader staying in place of the Overview after onboarding completes. - Dashboard: Hide the history upgrade prompt in the modernized Overview when My Jetpack is turned off, so it no longer leads to a page you cannot open. - Dashboard: Keep day details in the modernized Overview score history fully on screen, let the pointer move onto them, and show a focus ring on the chart. - Dashboard: Remove console errors and blank space under Critical CSS on sites that are not publicly available. - Dashboard: Restore button padding on the modernized Overview screen. - Dashboard: Restore the "Use license key" link beside upgrade prompts on the modernized dashboard. - Dashboard: Restore the padding around the upgrade, error, and welcome notices in the modernized Overview score history card. - Dashboard: Show Jetpack in-dashboard messages on the modernized dashboard. - Dashboard: Stop the modernized dashboard from logging a console error about missing Jetpack configuration. - Dashboard: Target contextual messages at the Boost screen on the modern dashboard. - Dashboard: Track Try again as a speed score refresh and keep keyboard focus on the page when a render failure removes the header button. - Defer JS: Keep scripts that come before a script left in place in their original order, fixing hidden product images and unclickable tabs on some sites using Jetpack Likes. - Footer: Hide Products and Help links when My Jetpack is unavailable. - Hide My Jetpack links when its admin page is unavailable. - Modern dashboard: Send the upgrade CTA to the Boost interstitial page instead of opening the modal. - My Jetpack: Fix the dashboard failing to load on WordPress.com-hosted sites. - My Jetpack: Fix the layout of the connection screen for right-to-left languages. - My Jetpack: Point users who cannot connect the site at an administrator, instead of an onboarding screen they cannot complete. - My Jetpack: Show each notice once instead of twice. - My Jetpack: Stretch the tab content background to the full height of the page. - Overview: Keep keyboard focus on the score history's first or last day instead of leaving the chart, and return focus to the chart when Escape closes a tooltip. - Overview: Let Tab move straight into and out of the score history while the pointer shows a day's details. - Overview: Let the pointer reach every day in the score history while a day's details are open, and leave a gap between the day and its details. - Overview: Let the pointer take over from the arrow keys in the score history, instead of flickering between the hovered and selected days. - Overview: Match the score help popovers, score history day details and paging tooltips to the design. - Overview: Show a day's score details on hover again after paging the score history with the keyboard. - Overview: Show a focus ring on the score history day selected with the arrow keys. - Overview: Show an upgrade link when the score history upgrade prompt cannot load. - Overview: Show the first recorded day of performance history immediately after upgrading. - Overview: Show the score history's Previous and Next arrows in dark grey instead of blue, to match the rest of the page. - Overview: Stop the score history from swallowing keys it does not use, such as Page Down, and close a day’s details when the series it describes is hidden. - Page Cache: Show the module as running, without contradictory setup errors, on WP Cloud hosts such as Pressable that already cache pages. - Performance history: Load the Overview faster on sites with little or no score history. - Performance history: Show the recorded decimal LCP, TBT, and CLS values in the history chart tooltips instead of whole numbers. - Performance scores: Cancel pending background score requests while viewing a sub-page. - Settings: Add space between a module's description and its status notice in the modern dashboard. - Settings: Announce to screen readers whether the image quality options are expanded. - Settings: Avoid duplicate navigation when returning from a sub-page. - Settings: Close the Page Cache example and Cornerstone Pages warning tooltips with Escape, and the warning with a click elsewhere. - Settings: Give information icons an accessible name for screen readers. - Settings: Hide upgrade and license links when their My Jetpack screens are unavailable. - Settings: Let keyboard users open tooltips with Enter or Space and dismiss them with Escape. - Settings: Match notice text to the rest of the page. - Settings: Match the Customize pages list label, image quality toggle, and Critical CSS status to the design. - Settings: Match the Save buttons in the exceptions panels and Cornerstone Pages editor to the rest of the page. - Settings: Nest the settings section headings under the page heading for screen readers. - Settings: Show text links in the brand colour and enlarge the Critical CSS info icon in the modern dashboard. - Settings: Show tooltips in full on the modernized Settings page instead of cutting them off at the card edge. - Settings: Tighten the Cornerstone Pages list editor and match its text size and color to the rest of the page. - Settings: Use the same text size and color for the exceptions panels and Image CDN help text as the rest of the page. -------- [See the previous changelogs here](https://github.com/Automattic/jetpack/blob/trunk/projects/plugins/boost/CHANGELOG.md#changelog)