Convert PNG to ICO, Free
Files convert instantly in your browser. 100% private, any file size, no account needed.
Drop your PNG file here
or click to browse. Any file size.
Conversion runs entirely in your browser. Your file never leaves your device.
How to convert PNG to ICO
ICO is the format used for Windows application icons and browser favicons. A single .ico file can contain multiple image sizes stacked together (16x16, 32x32, 48x48, 256x256) so that Windows and browsers automatically pick the right size for each context. Converting a PNG to ICO creates this multi-size container from your source image, scaling it to each required size and embedding them all in one file. The conversion runs entirely in your browser using WebAssembly.
For web favicons, the recommended approach is to include both a multi-size .ico for maximum browser compatibility and separate .png files at specific sizes (192x192, 512x512) declared via link tags for modern browsers and PWA icons. The .ico file specifically targets the browser tab favicon and Windows taskbar icon behavior. Start with a clean, square PNG with a transparent background at 256x256 or larger for the best downscaling results.
Upload your source PNG
Drop a square PNG. Transparent backgrounds are supported and recommended for icons. Minimum recommended size is 256x256.
Select the sizes to include
Choose which sizes to embed in the ICO: 16x16, 32x32, 48x48, 64x64, 128x128, 256x256. For maximum compatibility, include all of them.
Convert locally
The WebAssembly ICO encoder generates the multi-size container in your browser. No upload occurs.
Download the ICO
Save the .ico file and place it at the root of your website as favicon.ico. Include link tags for additional PNG sizes.
Frequently asked questions
What size should my source PNG be for the best ICO results?
256x256 or larger. The converter scales down from the source, so starting large preserves more detail at each embedded size.
Why does a favicon.ico contain multiple sizes?
Different contexts need different sizes: browser tabs typically use 16x16 or 32x32, Windows taskbar icons use 32x32 or 48x48, and the Windows Start menu uses 256x256. A multi-size ICO lets the OS pick the right one.
Can I include a transparent background in the ICO?
Yes. ICO supports binary transparency (fully transparent or fully opaque) and true alpha transparency. PNG sources with alpha are converted with full alpha channel support.
Do modern browsers need an .ico file or just PNG?
Modern browsers support PNG favicons declared in link tags, but .ico at the root is the universal fallback. For maximum compatibility across all browsers and OS contexts, having favicon.ico at the root is recommended alongside PNG declarations.
What is the difference between ICO and ICON (macOS)?
ICO is the Windows format. macOS uses the ICNS format. For cross-platform applications, both need to be generated separately.