ICO vs PNG favicon — which should you use?
A favicon is the small icon shown in a browser tab, bookmarks bar, and on mobile home screens. There are two common file formats: ICO and PNG. This guide explains the difference and when to use each.
Generate your favicon free →Quick answer
- Use ICO if you want maximum backward compatibility with one file:
favicon.ico. - Use PNG for sharper icons on modern sites, app icons, and multi-size setups.
- Best practice: ship both — an ICO fallback plus PNG (and ideally SVG) for modern browsers.
ICO vs PNG at a glance
| Feature | ICO | PNG |
|---|---|---|
| Browser support | Universal (including old IE) | All modern browsers |
| Multiple sizes in one file | Yes (16/32/48…) | One size per file |
| Sharpness | Good | Excellent |
| Transparency | Yes | Yes (full alpha) |
| Typical use | favicon.ico fallback | Modern sites, app icons |
What is an ICO file?
ICO is the original favicon format. A single .ico file can contain several sizes of the same image, which is why it remains the safest fallback for older browsers. Place it at the root of your site as /favicon.ico and most browsers will find it automatically.
What is a PNG favicon?
PNG offers lossless quality and full transparency. It looks sharper at small sizes on modern high-DPI screens. Because a PNG only holds one size, you typically reference several PNGs (16×16, 32×32, 180×180, 192×192, 512×512) in your HTML.
Recommended setup
For a modern site that still supports older browsers, add these tags to your <head>:
<link rel="icon" href="/favicon.ico" sizes="any"> <link rel="icon" type="image/png" sizes="32x32" href="/favicon-32x32.png"> <link rel="icon" type="image/png" sizes="16x16" href="/favicon-16x16.png"> <link rel="apple-touch-icon" href="/apple-touch-icon.png"> <link rel="manifest" href="/site.webmanifest">
What size should a favicon be?
Start from a square image of at least 512×512 px. Large images downscale to sharp small icons; small images look blurry when upscaled. See the full favicon size guide for every recommended dimension.
Generate both formats for free
Our free favicon generator converts an image into ICO and PNG in every standard size — right in your browser, with nothing uploaded to a server.
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