WordPress optimization plugins: WP Rocket coupon and Perfmatters coupon (25% off)

The WP Rocket coupon and the Perfmatters coupon are the same code: WPLIGHT. It gives 25% off WP Rocket and 25% off Perfmatters, two of the WordPress optimization plugins I run into most often in performance audits. You enter it in the discount code field at checkout on each plugin’s own site, wp-rocket.me and perfmatters.io. The discount is applied at checkout, so check the final price on that screen before you pay. The code works on both plugins, so you can buy one or the other, or both.

Affiliate disclosure: WPLIGHT is a partner code, and the WP Rocket and Perfmatters links on this page are affiliate links. If you buy through them I may earn a commission, at no extra cost to you. I still cover what each plugin does not do, and the free options, further down.

What do WordPress optimization plugins actually fix?

Most of them work on two layers. One is the page cache: the plugin saves the finished HTML of a page and serves that copy, so PHP and the database don’t run on every visit. The other is the front end: what the browser has to download, parse and execute before the page is usable. WP Rocket covers both. Perfmatters covers only the second, on purpose.

Neither one fixes slow hosting, a bloated database query on an uncached page, or a checkout that has to run PHP on every request. In audits I usually find the plugin was installed first and the structure was never looked at. A plugin is a good second step. The order I follow is in how to speed up WordPress, and the metrics these plugins are meant to move are covered in Core Web Vitals in WordPress.

What does WP Rocket do?

WP Rocket is a premium caching plugin with no free version. It runs on Apache, Nginx and LiteSpeed, and turns on page caching as soon as you activate it. Its documented features include:

• Page cache, with separate handling for mobile if you need it.
• Cache preload, which crawls your pages so the first visitor after a purge doesn’t hit an empty cache.
• File optimization: minifying CSS and JavaScript and loading JavaScript deferred.
• Delay JavaScript execution until the user interacts with the page.
• Remove unused CSS, which WP Rocket processes on its own servers and sends back to your site.
• Lazy load for images, iframes and videos.
• Database cleanup for revisions, drafts, trashed posts, spam comments and transients, with optional scheduling.
• CDN integration, by rewriting asset URLs to your CDN hostname.

What it does not do: it is not an object cache, so database queries on uncached requests (wp-admin, cart, checkout, logged-in users by default) still run in full. It has no script manager to switch off a plugin’s CSS and JavaScript on pages that don’t use them. And on a LiteSpeed server it competes with the server’s own cache, which is why I wrote a separate piece on WP Rocket vs LiteSpeed Cache. If you’re still picking a cache plugin, the best WordPress caching plugin guide sorts the options by server.

What does Perfmatters do?

Perfmatters is a lightweight premium plugin that does not include a page cache. It assumes something else is caching your pages, whether that’s a plugin, the server or an edge cache in front of the site. What it gives you is control over what loads:

• A script manager that disables individual CSS and JavaScript files, or a whole plugin’s assets, per page, per post type or sitewide. This is the feature I’d buy it for.
• Delay JavaScript until user interaction, either for scripts you list or for all of them with exclusions.
• Remove unused CSS.
• Preloading and fetch priority, so you can tell the browser which image or font matters first.
• Lazy load for images, iframes and videos.
• Local analytics, which serves the Google Analytics script from your own domain.
• Toggles that switch off WordPress features many sites never use, such as emojis, embeds, XML-RPC, Dashicons on the front end and the Heartbeat API.

I use Perfmatters on this site, with delay JavaScript, remove unused CSS and lazy load turned on. On sites with a page builder, a form plugin and a slider that only appear on a couple of pages, the script manager is where most of the cleanup happens.

What Perfmatters does not do: cache pages, compress images or touch the server. Install it alone on a site with no page cache and TTFB stays where it was. For how it sits next to image and cache plugins, see the best plugins for Core Web Vitals.

Should you use WP Rocket, Perfmatters or both?

It depends on what is already caching your pages. My rule of thumb:

• No page cache from the host and no LiteSpeed server: start with WP Rocket. It solves the cache and most of the front-end work in one plugin.
• The host already caches pages (server cache or an edge cache): Perfmatters is usually the better fit, because you don’t need a second page cache.
• Many plugins loading assets everywhere: add Perfmatters for the script manager, even if WP Rocket handles the cache.
• A small site with few plugins and good hosting: you may not need either. Try the free options in the FAQ first.

Running both is common and works fine, with one condition: each feature should be on in one plugin only. Two plugins delaying the same JavaScript or both rewriting CSS is how sites end up with broken menus and a cart that stops updating. When I set up the pair, I split it like this:

Which plugin gets the overlapping features is less important than keeping it consistent and testing after each change. Turn on one option, clear every cache, click through the menu, forms, search and checkout, then move to the next.

How do I use the WP Rocket discount code?

1. Go to wp-rocket.me and open the pricing page.
2. Pick the plan that matches the number of sites you need.
3. At checkout, find the coupon or discount code field and enter WPLIGHT.
4. Apply it and check that the 25% discount shows in the order total before you pay.
5. After payment, download the plugin from your WP Rocket account and install it under Plugins, Add New, Upload Plugin.

How do I use the Perfmatters discount code?

1. Go to perfmatters.io and open the pricing page.
2. Choose the plan for your number of sites.
3. At checkout, enter WPLIGHT in the discount code field and apply it.
4. Confirm the 25% discount in the total before you pay.
5. Download the plugin and your license key from your Perfmatters account, install the zip, then activate the license in the plugin settings.

Once either plugin is live, judge it by field data, not by one PageSpeed run. CrUX uses a 28-day rolling window, so give it a few weeks before you decide a setting helped or hurt.

Frequently asked questions

Does the WPLIGHT code work on renewals?

I can’t promise how renewals are priced, because that is set by each vendor. Check the renewal terms shown at checkout before you buy.

Can I use the code on both WP Rocket and Perfmatters?

Yes. WPLIGHT gives 25% off on WP Rocket and 25% off on Perfmatters. They are separate purchases on separate sites, so you enter the code once at each checkout.

Is there a free alternative?

Yes, for most of the work. On a LiteSpeed server, LiteSpeed Cache is free and covers page cache plus front-end options. On other servers, WP Super Cache, W3 Total Cache and Cache Enabler handle page caching. For unloading assets per page, Asset CleanUp has a free version. Free plugins usually ask for more setup time.

Will one of these plugins pass Core Web Vitals on its own?

Sometimes, on a simple site with decent hosting. When the server is slow or the page depends on heavy third-party scripts, the plugin helps but doesn’t close the gap. The thresholds are p75 field data: LCP at or under 2.5 s, INP at or under 200 ms and CLS at or under 0.1.

If you already run a cache plugin and the field data hasn’t moved, the cause is usually below the plugin layer: hosting, database, third-party scripts. That is what I look at in a WordPress performance audit, and the report tells you which fixes are worth doing before you buy anything else.