Make your site faster
Upload your site as it is; Fylo builds an optimized copy and serves that. Your original files are never modified and can always be downloaded. Every setting on the Performance tab is a switch you can turn off again, on every plan.
How it works
Choose a site at the top of the Performance tab. New sites start with Fylo's recommended settings already on (see Auto-speed optimization); after that everything is yours to change. Each change rebuilds the optimized copy — a few seconds on a small site, longer on one with many pages or images. A spinner shows while it runs.
Because the originals are untouched, the fix for any problem is always the same: switch the setting off.
Auto-speed optimization
When you're signed in, every new site gets Fylo's recommended speed settings automatically — on every plan, Free included. This applies to uploads from the dashboard, the homepage, the API and AI apps. A site uploaded without an account is published as-is until you sign up and it moves into your account.
Your link comes first. The upload finishes and your link works straight away; optimization then runs in the background. Until it's done, visitors get your original files — the site works exactly the same, it just isn't optimized yet. A Running auto-speed optimization in background message shows under your link on the upload screen and at the bottom of the dashboard, and changes to Auto-speed optimization complete when it finishes. You can close the page; it keeps running.
What it turns on:
| Area | Settings |
|---|---|
| Font | Self-hosted Google Fonts (full font), Preload fonts |
| CSS | Minify HTML & CSS |
| JS | Delay JavaScript in Defer mode, with reCAPTCHA, hCaptcha, Google Maps and payment scripts (Stripe, PayPal, Razorpay, Cashfree, PhonePe, Paytm) already in Never delay |
| Image | Image Optimization (WebP, quality 80), Responsive Images, Properly Size Images, Preload LCP image |
| Lazy Load | Lazy Load Images, Lazy Load Iframes & Videos, Lightweight YouTube Previews |
Left off on purpose, because they can change how a site behaves: font subsetting, inlining stylesheets and self-hosting external CSS/JS. Turn them on yourself if you want them.
Auto-speed runs once per site, on its first upload. Replacing the files later keeps whatever settings the site has — including anything you changed — and rebuilds the optimized copy. Converted images count towards your monthly image quota, the same as when you switch the setting on yourself.
If optimization can't finish, it retries automatically. If it still fails you'll see Auto-speed optimization could not finish — your site stays live with your original files, and you can switch settings on from this tab.
Turn auto-speed off
Go to Settings → Features and switch off Auto-speed optimization. New uploads are then published as-is, and you can still switch on any setting per site on the Performance tab. The switch only affects new uploads: sites you already have keep their settings, and turning auto-speed back on later doesn't change sites you uploaded while it was off.
Font
| Setting | What it does |
|---|---|
| Self-hosted Google Fonts | Serves Google Fonts from your own domain instead of fonts.googleapis.com, removing two third-party connections from the critical path. |
| Font delivery | Full font keeps everything. Subset ships only the characters your pages use — typically 40–60% fewer font bytes. System fonts ships no font at all; the site renders in each visitor's default typeface. |
| Preload fonts | Starts the font download immediately instead of waiting for the stylesheet. Needs self-hosted fonts. |
| Font display swap | Always on: text shows at once in a fallback font while web fonts load. |
Use Full font if scripts insert text after the page loads or visitors type into forms in a web font — a subset only contains characters found in your HTML.
CSS
| Setting | What it does |
|---|---|
| Minify HTML & CSS | Strips whitespace and comments. |
| Inline small stylesheets | Puts stylesheets under 15 KB straight into the page, removing a render-blocking request. Larger ones stay external. |
JS
| Setting | What it does |
|---|---|
| Delay JavaScript | Holds your scripts until the browser is idle or the visitor first interacts (scroll, tap, key press), or simply defers them. Cuts blocking time and speeds up first paint. |
| Never delay | Scripts to leave alone, one per line — part of a file name is enough (pdf.min.js). |
| Self-host external CSS/JS | Downloads third-party CSS and JS to your own domain so the browser makes fewer connections. Exclude libraries that load their own extra files. |
Delay JavaScript is the setting most likely to change behaviour. If a menu, slider or animation that should work on load stops working, add its script to Never delay or choose Defer.
Image
| Setting | What it does |
|---|---|
| Image Optimization | Converts PNG, JPG and GIF to WebP and serves them from your domain. SVG and AVIF are left alone, and an image that would get bigger keeps its original. |
| Quality | 40–90, default 80. Lower is smaller. |
| Responsive Images (srcset) | Creates smaller copies of large images so phones download a phone-sized file. |
| Properly Size Images | Adds width and height to image tags so the page doesn't jump while loading (layout shift). |
| Preload LCP image | Fetches your main above-the-fold image first. Detected automatically, or name the file. |
| Exclude | Any image setting can skip files: one name or keyword per line. |
Each image Fylo converts counts towards a monthly quota; the meter is on the Image tab and resets each month.
| Plan | Images optimized per month |
|---|---|
| Free | 10 |
| Starter | 100 |
| Pro | 1,000 |
| Business | 5,000 |
Only real conversions count, and every size that Responsive Images generates is one image. An image that hasn't changed is not converted again when the site rebuilds, so re-uploading the same site or flipping another setting doesn't use quota. When the quota runs out, the remaining images are served as their originals until next month. Optimize images now re-runs conversion after you change quality or exclusions.
Lazy Load
| Setting | What it does |
|---|---|
| Lazy Load Images | Loads images only as they scroll into view. Exclude your hero image so it is never delayed. |
| Lazy Load Iframes & Videos | Does the same for maps, embeds and videos. |
| Lightweight YouTube Previews | Replaces each YouTube embed with a thumbnail that loads the real player on click. One embed can outweigh the rest of the page. |
A sensible order
- Minify, self-hosted fonts, Image Optimization, Properly Size Images, Lazy Load Iframes, YouTube previews — safe on almost every site.
- Responsive Images and Preload LCP — check the hero image still looks sharp.
- Delay JavaScript, font subsetting, Lazy Load Images — test the site after each.
Measure before and after with the Website Speed Checker.
From an AI app
With the MCP server connected, "turn on WebP images and lazy-load iframes for my portfolio" changes the same settings and reports what was saved.
Try it on your site
Everything here is in your dashboard. The free plan needs no card.
Open the dashboard