What does this tool check?
Enter a URL and the tool inspects it against the full modern favicon spec: the classic favicon.ico, 16×16 and 32×32 PNG icons, the Apple touch icon used on iOS home screens, a web app manifest with 192×192 and 512×512 icons for Android/PWA installs, a theme colour meta tag, and the older Windows tile format. Each one is fetched and verified – not just checked for a matching <link> tag – so broken links and wrong-sized images are caught, not just missing ones.
How does the "fix these issues" step work?
Once the check finishes, the tool only asks you for what's actually missing or broken. Upload one square source image and it's resized in your browser into exactly the files needed to fix those issues – nothing is regenerated if it's already working. You get a ZIP file of the new files plus the exact <link>/<meta> lines to add, and only those lines.
Is my image uploaded anywhere?
No. Resizing, the favicon.ico packing and the ZIP file are all built directly in your browser using the canvas API – the source image never leaves your device. The URL check step does fetch your target site's existing favicon files from our server in order to verify them, since that's the only way to confirm they're actually reachable.
Why do I need so many favicon files?
Different browsers and platforms each request their own preferred format: Chrome and Firefox tabs use small PNGs (or the favicon.ico fallback), iOS home screen bookmarks use the Apple touch icon, and Android "Add to Home Screen" plus installable PWAs read icon sizes from the web app manifest. Missing any one of these doesn't break the site, but it does mean your icon is missing or blurry in that specific context.
My site already has a favicon.ico – why is it flagged?
Browsers request /favicon.ico automatically even when a page also declares modern <link> icons, so it's worth keeping as a fallback. If your site already serves working 32×32 PNG icons instead, a missing favicon.ico is flagged as a low-priority issue rather than a broken one.