FAQ / Help

What does PageSpeedBooster actually do?

It combines 30+ WordPress optimizations in one plugin: page cache, browser cache, HTML/CSS/JS minification, defer and delay JavaScript, lazy-load images, WebP conversion, Google Fonts optimization, WordPress bloat removal (emojis, Dashicons, jQuery Migrate, oEmbed, XML-RPC, Heartbeat, Gutenberg CSS, Global Styles), .htaccess cache rules, database cleanup, preload hints, Instant Page prefetch, and a built-in PageSpeed Insights benchmark tool.

Will it improve my Google PageSpeed score?

Yes. After enabling default settings — page cache, HTML/CSS/JS minification, lazy load, defer JS, and browser cache — most sites see a meaningful increase in their PageSpeed Insights score. The exact gain depends on your theme, hosting, and existing bottlenecks. Use the built-in before/after benchmark tool (PageSpeed Comparison section) to measure the impact directly from your WordPress dashboard.

Do I need to configure anything?

No. Install, activate, and click Save Changes. The safe defaults (page cache, minification, lazy load, defer JS) work on most sites out of the box. Then use the Clear All Cache button to apply changes immediately. More aggressive options (delay JS, optimize CSS delivery, Critical CSS) are available for further tuning but are off by default.

What are the minimum requirements?

WordPress 6.0 or higher, PHP 7.4 or higher. The plugin works on any standard Apache or Nginx shared host — no special server software required (unlike LiteSpeed Cache, which requires a LiteSpeed server for its best features).

How does the Page Cache work?

When a visitor loads a page, the plugin saves the full rendered HTML as a static file in wp-content/cache/pagespeed-booster/. Subsequent visitors receive that static file directly — bypassing PHP and the database entirely. Cached pages include a comment at the bottom: "PageSpeedBooster Cache | generated in Xms | cached at [date]" so you can verify it is working. Cache is automatically skipped for logged-in users and is cleared when you save settings or click Clear All Cache.

How do I confirm the cache is working?

Open your site in an incognito/private window (so you are not logged in), visit a page, then reload it. View the page source (Ctrl+U) and look for the PageSpeedBooster Cache comment near the bottom of the HTML.

Does the page cache work for logged-in users?

No. The page cache is intentionally skipped for logged-in users to avoid serving stale admin bars or user-specific content. Logged-in visitors always get fresh PHP responses.

What are Browser Cache Headers?

The plugin adds Cache-Control HTTP headers to your pages so that browsers store assets locally for repeat visits. Combined with the .htaccess Browser Cache option (which injects mod_expires rules for static assets like images, CSS, and JS), returning visitors load your site much faster without downloading resources they already have.

Does it replace W3 Total Cache or WP Super Cache?

Yes. PageSpeedBooster includes its own page caching engine. It is recommended to deactivate other caching plugins before enabling the Page Cache option to avoid conflicts. If you prefer to keep another caching plugin, simply leave the Page Cache option disabled and use the other optimizations independently.

What is the difference between Defer JS and Delay JS?

Defer JavaScript adds the defer attribute to script tags, which tells the browser to load scripts after the HTML is parsed — preventing render-blocking. Delay JavaScript goes further: it postpones script execution entirely until the user first interacts with the page (a click, scroll, or keypress). Delay JS gives the best improvement to Time to Interactive and INP, but some scripts (like chat widgets or sliders) may need to be excluded if they must load immediately.

What does "Optimize CSS Delivery" do?

This Premium feature defers render-blocking stylesheets using the media="print" trick combined with a preload link, so the browser fetches CSS without blocking rendering. It works best when paired with Critical CSS, which inlines only the above-the-fold styles so the page renders visually complete before the full stylesheet loads.

What is Critical CSS and is it automatic?

Critical CSS (Premium) is the minimal subset of your stylesheet required to render the above-the-fold portion of a page. PageSpeedBooster generates it automatically via a remote server — no Puppeteer or CLI setup required on your hosting. It then inlines the critical styles in the <head> and defers the full stylesheet, significantly improving Largest Contentful Paint (LCP).

What does Remove Query Strings do?

WordPress appends version numbers to CSS/JS URLs (e.g. style.css?ver=6.4). These query strings prevent some CDNs and proxies from caching the files. This option strips them so the URLs are cache-friendly.

How does WebP conversion work?

When you upload an image to the WordPress Media Library, PageSpeedBooster automatically creates a .webp version alongside the original. The plugin then serves the WebP file to browsers that support it (all modern browsers). WebP images are typically 25–35% smaller than JPEG/PNG, reducing page weight and improving load time. Originals are kept for compatibility.

What does Lazy Load Images do?

It adds the native loading="lazy" attribute to all images that do not already have it. The browser then defers loading of off-screen images until the user scrolls near them, reducing initial page weight and improving LCP for above-the-fold content.

What WordPress bloat does the plugin remove?

You can selectively disable: the WordPress emoji script and inline styles, the oEmbed script (removes one HTTP request), jQuery Migrate (legacy compatibility shim rarely needed on modern themes), Dashicons (font icon set loaded for logged-out visitors), the Gutenberg block editor CSS on the front end (if your theme does not use blocks), the Global Styles inline block (large inline JSON injected by WordPress core), and unused head tags like RSD links and shortlinks via Clean Head.

Is it safe to disable jQuery Migrate?

For most modern themes and plugins, yes. jQuery Migrate only provides backwards compatibility for very old jQuery code. Test your site after disabling it — if your slider, gallery, or form breaks, simply re-enable it.

What does Disable XML-RPC do?

XML-RPC is a legacy WordPress API used by older mobile apps and some plugins. It is a common attack vector for brute-force login attempts. Disabling it blocks all XML-RPC requests via a filter, improving security without affecting normal site operation. Note: Jetpack and some backup plugins use XML-RPC — check compatibility before enabling this.

What does Limit Heartbeat do?

The WordPress Heartbeat API sends periodic AJAX requests from the browser to the server (by default every 15 seconds in the admin). This option reduces the frequency or disables Heartbeat entirely on the front end, reducing unnecessary server load and database queries.

What does Optimize Fonts do?

It adds display=swap to Google Fonts requests so text renders immediately in a fallback font while the web font loads — preventing the invisible-text flash (FOIT) that hurts CLS and LCP. It also adds a preconnect hint to fonts.googleapis.com and fonts.gstatic.com to speed up the connection.

What is Instant Page?

Instant Page uses the instant.page library to prefetch pages when a user hovers over or starts touching a link, before they actually click it. By the time the click happens, the page is already loading (or loaded) in the background, making navigation feel near-instant.

What does Preload Key Links do?

You can specify critical resources (fonts, hero images, key scripts) to be preloaded with <link rel="preload"> hints in the <head>. This tells the browser to fetch those assets at the highest priority, improving LCP and reducing perceived load time.

What is the PageSpeed Comparison tool?

It is a built-in before/after benchmark inside your WordPress dashboard. Enter a URL and your Google PageSpeed Insights API key, then run the test. The tool clears the cache, warms it, waits a configurable delay, then fires two API calls (before and after) and displays the performance score difference with core metrics (LCP, TBT, CLS, Speed Index, FCP).

How do I get a Google PageSpeed Insights API key?

Go to console.cloud.google.com, create a project, enable the PageSpeed Insights API, then go to APIs & Services → Credentials and create an API key. The free tier allows 25,000 requests per day, which is more than enough for regular benchmarking. Paste the key in PageSpeedBooster → Settings → PageSpeed API Key.

What does Database Optimization do?

It cleans up WordPress database overhead: removes post revisions, draft auto-saves, trashed posts, expired transients, and spam/trashed comments. It then runs OPTIMIZE TABLE on all WP tables to defragment and reclaim disk space. This can speed up database queries, especially on older or heavily-edited sites.

What features are free vs. Premium?

All core features are free: page cache, browser cache, .htaccess rules, HTML/CSS/JS minification, defer JS, delay JS, lazy load, WebP conversion, all WordPress bloat removal options, Instant Page, font optimization, remove query strings, preload hints, database optimization, and the PageSpeed benchmark tool. Premium features are: Critical CSS (auto-generated above-the-fold CSS) and Optimize CSS Delivery (async stylesheet loading). Premium requires a license key.

How do I activate my Premium license?

After purchasing, you will receive a license key by email. In WordPress, go to PageSpeedBooster → License, paste the key into the License Key field, and click Activate. The plugin verifies the key with pagespeedbooster.com and unlocks Premium features immediately.

My "With Plugin" and "Without Plugin" PageSpeed scores look the same — why?

Make sure you are not logged in when running the comparison, as the page cache is disabled for logged-in users. The comparison tool clears the cache, warms it, then runs both tests — allow the full cycle to complete before comparing results. Also ensure your Google PageSpeed API key is set correctly.