ICO is the Windows icon container format. A single .ico file can hold several image sizes so the operating system or browser can pick the sharpest one for each context, such as a 16px tab favicon or a 48px desktop shortcut.

Which sizes should I include?

For a website favicon, 16, 32 and 48px covers almost everything. Add 64, 128 or 256px if you also want a crisp desktop or taskbar icon.

Are my images uploaded anywhere?

No. The conversion runs entirely in your browser using the canvas API, so your PNG never leaves your device.

PNG to ICO Converter

Turn a PNG into a multi-size Windows .ico favicon — in your browser.

PNG to ICO — make a Windows favicon in your browser

Convert a PNG into a Windows .ico icon with multiple sizes baked into one file. The converter draws your image at each size you pick — 16, 32, 48px and up — and bundles them into a single multi-resolution .ico, so browsers and Windows always have a sharp icon to show.

Everything runs locally in your browser. Your images are never uploaded.