ICO Converter
Convert your images to ICO format with our free online ICO converter. Perfect for creating favicons, app icons, and Windows icons.
What is ICO?
ICO (Icon) is a file format used for icons in Microsoft Windows. ICO files contain one or more small images at multiple sizes and color depths, such that they may be scaled appropriately. The most common use of ICO files is for favicons on websites, but they're also used for desktop icons, application icons, and other user interface elements.
ICO Format Features
- Multiple Sizes: Can contain multiple image sizes in one file (16x16, 32x32, 48x48, etc.)
- Transparency Support: Supports alpha channel transparency
- Color Depths: Supports various color depths from 1-bit to 32-bit
- Windows Integration: Native support in Windows operating system
- Web Favicon Standard: Standard format for website favicons
- Backward Compatibility: Supported by all browsers and Windows versions
- Compression: Can use PNG compression for better quality
When to Use ICO
Best For:
- Website favicons
- Windows desktop icons
- Windows application icons
- Browser bookmarks
- Windows Start menu tiles
- Legacy system compatibility
- Windows Explorer thumbnails
- Desktop shortcuts
Consider Alternatives:
- Modern web favicons (PNG/SVG)
- Mobile app icons (PNG)
- High-resolution displays (SVG)
- Cross-platform applications
- Modern Progressive Web Apps
- Vector graphics requirements
Common ICO Sizes
Professional ICO files often include multiple sizes for optimal display across different contexts and screen resolutions.
Favicon Implementation
HTML Implementation
Place your favicon.ico file in the root directory of your website for automatic detection by browsers.
ICO vs Other Icon Formats
| Feature | ICO | PNG | SVG |
|---|---|---|---|
| Multiple Sizes | ✓ Built-in | ✗ Single size | ✓ Scalable |
| Browser Support | Universal | Universal | Modern |
| Windows Integration | ✓ Native | Limited | ✗ No |
| File Size | Large | Medium | Small |
| Quality | Good | Excellent | Perfect |
How to Convert to ICO
- Go to our image converter tool
- Upload your image (recommended: square format, 256×256 or larger)
- Select “ICO” as your output format
- Our tool will automatically create multiple sizes within the ICO file
- Click “Convert Images” to start the conversion
- Download your converted ICO file
- Place the favicon.ico file in your website's root directory
Tip: For best results, start with a square image at least 256×256 pixels. Simple, high-contrast designs work best for small icon sizes.
ICO Technical Specifications
- File Extension
- .ico
- MIME Type
- image/x-icon, image/vnd.microsoft.icon
- Maximum Images
- 255 images per file
- Maximum Size
- 256×256 pixels (standard)
- Color Depth
- 1, 4, 8, 16, 24, 32 bits
- Compression
- BMP or PNG encoding
ICO Design Best Practices
- Use simple, recognizable designs that work at small sizes
- Ensure high contrast between foreground and background
- Avoid fine details that disappear at 16×16 pixels
- Test your favicon at different sizes and on different backgrounds
- Use solid colors rather than gradients for better clarity
- Consider your brand colors and ensure they work as a small icon
- Make sure the icon is recognizable even when very small
- Keep transparency areas clean and intentional
Modern Favicon Strategy
Comprehensive Approach
- • favicon.ico: For legacy browser support and Windows integration
- • PNG icons: For modern browsers with better quality
- • SVG favicon: For vector scalability on modern browsers
- • Apple Touch Icons: For iOS devices and PWA support
- • Web App Manifest: For Progressive Web App integration
While ICO is still important for compatibility, a modern strategy includes multiple formats for the best user experience across all devices and browsers.
Ready to Create ICO Favicons?
Start converting your images to ICO format now and create professional favicons for your website or application.
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