Favicon Generator
A favicon is the small icon displayed in browser tabs, bookmarks, and history. The ICO format bundles multiple sizes into one file so the browser can pick the appropriate resolution for each context: 16x16 for tabs, 32x32 for taskbar pins, and 48x48 for desktop shortcuts.
This tool generates a multi-size ICO favicon from any image directly in your browser. No upload required.
How favicon ICO files work
The ICO format is a container, not a compression format. Each ICO file contains a directory header listing its frames, followed by the frame data. Modern ICO files use PNG compression for each frame, which keeps file sizes small (typically 5-15 KB for a three-size favicon) while supporting full 32-bit color with transparency.
When a browser requests a favicon, it reads the ICO directory and selects the frame closest to the size it needs. This is why bundling multiple sizes matters: a 16x16 icon designed for a browser tab looks crisp at that size, while a scaled-down 48x48 icon might lose important details.
How to use
- Drop or click to upload any image (PNG, JPG, SVG, or other formats work)
- The tool generates a favicon.ico containing 16x16, 32x32, and 48x48 frames
- Download the ICO file
- Place it at your site’s root as
/favicon.ico
Tips for good favicons
Start with a square source image of at least 512x512 pixels. Simple, bold designs work best because the icon will be viewed at very small sizes. Avoid fine text or thin lines that disappear at 16x16. Test your favicon at actual size in a browser tab before deploying.
If you need to convert other image formats first, use the Image Converter to prepare your source image. For embedding a favicon directly in HTML as a data URI, convert it with the Base64 Encoder.