🔖 ICO Format
ICO Converter
Convert ICO files in your browser. Free, private, and fast. Create favicons from PNG or JPG, or extract icons to PNG — and link to the best ICO import and export pages.
What is ICO?
ICO is the icon container format used by Windows and by every website favicon. A single ICO file can hold multiple image sizes (16×16 up to 256×256) so the operating system or browser can pick the sharpest variant for the context.
Common uses for ICO
- Website favicons served as /favicon.ico
- Windows application and shortcut icons
- Toolbar and system-tray icons at multiple sizes
Note: ICO is only meant for small icons — images are capped at 256×256 pixels, so it is unsuitable as a general-purpose image format.
Compatibility: Universal favicon support in every browser. Windows native. Most image editors need a plugin to save ICO.
100% Private & Browser-Based
Your files never leave your device. All conversion happens locally in your browser — nothing is uploaded to any server. No sign-up required.
FAQ
Frequently Asked Questions
Yes — all ICO conversion tools on AintoB are completely free. No account required, no upload limits for typical files.
ICO is the icon container format used by Windows and by every website favicon. A single ICO file can hold multiple image sizes (16×16 up to 256×256) so the operating system or browser can pick the sharpest variant for the context.
Your ICO files are processed entirely in your browser. Nothing is sent to any server — the conversion is performed locally using browser-native APIs.
ICO stands for Windows Icon Format. ICO is the icon container format used by Windows and by every website favicon.