ICO Converter
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Convert ICO to other formats
What is ICO?
ICO is an icon format used by Windows. It can contain multiple sizes of the same image in one file, so the icon looks good at different sizes.
History
The ICO format has been used since the early versions of Windows. It remains the standard for website favicons and Windows application icons.
Key Features
- Can store multiple resolutions (16x16, 32x32, 48x48, etc.)
- Supports transparency
- Small file size
- Not suitable for photographs
Compatibility
ICO files are mainly used for favicons on websites and icons in Windows programs. They can be opened by most image viewers but are not meant for regular photos.
Pros & Cons
✅ Advantages
- Stores multiple sizes in a single file
- Standard for Windows program icons and favicons
- Supports transparency
❌ Disadvantages
- Very small maximum dimensions (typically 256x256)
- Limited color palette in classic ICO
- Not suitable for photographs or detailed images
How to Open & Edit ICO Files
Windows
- Open with built‑in icon viewer or any image viewer
- Edit with IcoFX, Greenfish Icon Editor Pro, or online converters
macOS / Linux
- View in most image viewers (Preview may not support .ico)
- Edit with GIMP or an online ICO editor
Recommended Tools
IcoFXGreenfish Icon Editor ProGIMP (with plug‑in)Online ICO converter
Version History
- ▹1985: ICO format introduced with Windows 1.0
- ▹1990s: Extended to support multiple sizes and color depths
- ▹2000s: PNG compression allowed within ICO files
- ▹Today: Still the standard for favicons and Windows icons
Common Conversion Scenarios
Extract a high‑resolution icon as a normal image
PNG preserves transparency and full color
Convert to PNG →Frequently Asked Questions
1Can I convert a photo to ICO?
Yes, but it will be reduced to a very small size. ICO is for icons, not for photos. Use PNG or JPG for regular images.
2How do I use the ICO file as a favicon?
Upload the ICO file to your website's root folder and add <link rel="icon" href="favicon.ico"> to your HTML.