Do I need multiple WordPress performance plugins?

Open the Plugins page on a WordPress site that’s a few years old and you’ll often find a small collection: one plugin for caching, one for minification, one for lazy loading, one for images, maybe another for fonts. Each was added for a good reason. Together, they’re often the reason the site isn’t as fast as it should be.

So, do you really need all of them? With FastPixel, definitely not. It covers all parts of WordPress front-end optimization in one place, which means you can retire most overlapping performance plugins. There’s one plugin it runs happily alongside, though: ShortPixel Image Optimizer.

Here’s why that is, and how to set the two up.

Table of Contents

Why a bigger plugin stack rarely means a faster site

It’s an easy trap. One plugin caches the page, another minifies CSS, a third handles lazy loading, and each one promises a few more points on PageSpeed Insights. The trouble is that they all work on the same thing: the HTML, CSS, JavaScript and images of the same page.

When several tools touch the same output, a few things tend to happen:

Overlap. Two plugins minify the same file, or two plugins lazy load the same image. You pay the processing cost twice and gain nothing.
Conflicts. Cache layers can serve stale or half-optimized pages when they disagree about who’s in charge. This is why FastPixel recommends deactivating other caching plugins when you switch to it.
Harder debugging. When the menu stops working, which plugin broke it? With five candidates, you’re toggling settings for an afternoon.
More weight. Every plugin is itself code that loads, runs and adds settings, scheduled tasks and database entries. We covered this slow creep in Why WordPress Websites Get Slower Over Time.

The answer isn’t more tools. It’s fewer tools that each do a distinct job.

What FastPixel already does for you

FastPixel is built as one plugin that handles page caching, CSS and JavaScript optimization, adaptive image delivery, database cleanup and more. Here’s what that means in plugin terms:

The job	The plugin you’d normally add	In FastPixel
Page caching	A caching plugin	Built in, with cache warmup and stale-while-revalidate logic
HTML, CSS and JS minification	A minification or “asset optimizer” plugin	Built in, served from the CDN
Critical CSS	A Critical CSS or render-blocking CSS plugin	Generated automatically
JavaScript delay	A script-delay plugin	Built in, with exclusions and GDPR-safe handling
Font optimization	A font-loading plugin	Built in, with DNS preconnect and preloading
Responsive and next-gen images	An adaptive images plugin	Built in, with resizing, cropping and WebP/AVIF conversion
CDN	A separate CDN plugin or service	Built in CDN
Database cleanup and WordPress de-bloating	A cleanup plugin	Built-in tools
Object cache	An object cache drop-in	Supported directly

The point isn’t that every one of these is a checkbox. It’s that they’re designed to work as one pipeline, so nothing is processed twice and nothing fights over the same file.

What FastPixel doesn’t replace are plugins that have nothing to do with front-end speed: security, backups, SEO, forms, your page builder. Those aren’t competing for the same job, so they can stay.

The exception: FastPixel and ShortPixel Image Optimizer

There is one pairing we’re happy to recommend. ShortPixel Image Optimizer (SPIO) and FastPixel can work well together because their main roles are different.

SPIO works on the files. It compresses the images in your Media Library, can generate WebP and AVIF versions, keeps a backup of the originals, and can even write ALT text, captions and descriptions for image SEO. The result is smaller files on your server and less disk space used.
FastPixel works on site optimization and delivery. It resizes and crops images to fit their placeholders, converts them to next-gen formats, serves them adaptively from the CDN, and handles caching and the rest of the page optimization.

Because SPIO focuses on permanently optimizing the files stored in your Media Library, while FastPixel focuses on optimization and delivery to visitors, they can complement each other without needing separate plugins for the same performance tasks.

Here’s the workflow we described in FastPixel vs ShortPixel Image Optimizer:

Run SPIO on your Media Library first.
Once you’re happy with the results, remove SPIO’s backup folder to save disk space.
Let FastPixel handle on-the-fly delivery and optimization from there.

One tip: avoid compressing aggressively twice. A common combination is Lossy or Glossy in SPIO and Lossless in FastPixel, which keeps the balance between speed and quality. And you don’t need ShortPixel Adaptive Images alongside it, since adaptive images are already included in FastPixel.

Not sure which side of the line you’re on? Our docs cover what to choose between FastPixel and ShortPixel.

How to set it up

A clean setup takes a few minutes:

Install FastPixel and deactivate any other caching or front-end optimization plugins you were using, such as separate minification, lazy-load or Critical CSS plugins.
Pick your JavaScript mode in the plugin settings. Delay non-critical JavaScript is the fastest option and the one we recommend; Optimize JavaScript is the most compatible.
Purge the full cache. Changes in the JavaScript, Images and Fonts tabs only apply after a full purge.
Test the pages that matter on your phone: homepage, a key landing page, and the cart and checkout if you run a store. If something misbehaves, exclude only that script or page.
Keep SPIO active for your Media Library if you use it, and leave the rest of the image delivery to FastPixel.

Want to see the difference before changing anything? You can run a test on test.fastpixel.io without installing anything. It optimizes a copy of your site, so your live site stays untouched.

The bottom line

You generally don’t need a separate caching plugin, minifier, lazy-loader, Critical CSS tool or CDN plugin alongside FastPixel. FastPixel does those jobs in one place, and doing them in one place is often exactly what makes the site faster and easier to maintain.

One plugin you may still want to keep alongside it is ShortPixel Image Optimizer, because it handles a different layer: the files themselves. Use SPIO for what’s stored, FastPixel for everything that’s served.

FastPixel is free on sites under 1,000 page views a month, so there’s no cost to trying it.

FAQs

Do I need other performance plugins if I use FastPixel?

No. FastPixel covers page caching, CSS and JavaScript optimization, Critical CSS, fonts, adaptive images and CDN delivery. We recommend deactivating other caching plugins when you switch, to avoid conflicts.

Can I use FastPixel with ShortPixel Image Optimizer?

Yes. SPIO optimizes the image files in your Media Library, while FastPixel optimizes how pages and images are delivered to visitors. Their main roles are different, so they can complement each other.

Do I need ShortPixel Image Optimizer to use FastPixel?

No. FastPixel already includes image optimization and adaptive delivery. SPIO is useful if you also want to permanently optimize the image files stored in your WordPress Media Library.

Do I need ShortPixel Adaptive Images as well?

No. Adaptive image delivery is already included in FastPixel.

Which image compression level should I use if I run both?

A common combination is Lossy or Glossy in ShortPixel Image Optimizer and Lossless in FastPixel, so images aren’t compressed aggressively twice.

Which plugins can stay alongside FastPixel?

Plugins that don’t overlap with front-end optimization, such as security, backup, SEO and form plugins. If you suspect a conflict, the Diagnostics tab in FastPixel shows plugin conflicts and the plugin’s status.