What is the ICO file format?

ICO is a Windows icon container format that can store multiple images at different resolutions and colour depths in a single file. Modern ICO files use embedded PNG data. The OS or browser picks the most appropriate resolution for each display context.

Which sizes should I include in my favicon?

For a standard web favicon, include at minimum 16px, 32px, and 48px. Modern browsers also use 64px and 128px for high-DPI displays. 256px is used by Windows for large icon views. The Minimal preset (16, 32, 48) is sufficient for most websites.

Does the tool support transparent backgrounds?

Yes. The image is drawn on a transparent HTML5 canvas and exported as PNG, preserving alpha transparency. Your ICO file will have a transparent background if your source image does.

What image formats can I convert?

Any image format the browser can display: PNG, JPG, WebP, GIF, SVG, and BMP. For favicon use, PNG with a transparent background is recommended.

Is my image uploaded to a server?

No. The entire conversion process: resizing, PNG encoding, and ICO assembly: happens in your browser using the Canvas API. Your image never leaves your device.

How do I use the generated .ico file?

Place favicon.ico at the root of your website (https://example.com/favicon.ico). Browsers will find it automatically. You can also reference it explicitly with: .

Can browsers display PNG favicons directly without ICO?

Yes. Modern browsers support PNG favicons referenced with . An ICO file is still recommended for broad compatibility, particularly with older browsers and Windows system integrations.

Why does my icon look blurry at small sizes?

High-resolution images with fine detail do not scale down well. For small sizes (16px, 24px), consider using a simplified version of your logo: a single letter or bold symbol works better than a detailed illustration.

What is the difference between favicon.ico and apple-touch-icon?

favicon.ico is used by browsers for browser tabs and bookmarks. Apple Touch Icons (apple-touch-icon.png, typically 180px) are used by iOS when a user saves your site to their home screen. They are different files serving different purposes.

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PNG to ICO Converter

Convert any image to a multi-resolution .ico file. Choose which sizes to embed (16–256px). 100% browser-based.

Drop an image here or click to browse

PNG, JPG, WebP, SVG supported

Sizes to include

6 sizes selected

Your .ico file will appear here

Upload an image and click Generate

About .ICO format

Modern ICO files embed PNG data directly inside a binary container. Windows, macOS, and all major browsers support PNG-in-ICO. Including multiple sizes lets the OS pick the best resolution for each display context (taskbar, desktop shortcut, browser tab).

Creating multi-resolution ICO favicons

A favicon.ico file at the root of your website is the universal way to set a site icon. Modern ICO files embed PNG images at multiple resolutions so the operating system can pick the most appropriate size: 16px for browser tabs, 32px for taskbar pinned sites, and 256px for Windows file explorer.

This tool builds multi-resolution ICO files entirely in your browser. Upload any image, select which sizes to include, and download a binary-correct ICO container with PNG data embedded for each chosen resolution. No server upload required.

Step-by-step guide

1
Upload your image
Drag and drop or click to browse. PNG, JPG, WebP, and SVG are all supported. For best results use a square image.
2
Select ICO sizes
Choose which resolutions to embed: 16, 24, 32, 48, 64, 96, 128, or 256 pixels. Use All for a full multi-resolution icon, or Minimal (16, 32, 48px) for a smaller file.
3
Click Generate .ICO
The browser resizes your image to each selected size using Canvas and bundles the PNG data into an ICO container.
4
Preview at each size
See how your icon looks at each resolution before downloading. Small sizes (16px, 24px) may require a simpler design.
5
Download the .ico file
Click Download .ico to save the file. Place it at the root of your website or reference it with a link rel='icon' tag.

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Frequently Asked Questions

What is the ICO file format?: ICO is a Windows icon container format that can store multiple images at different resolutions and colour depths in a single file. Modern ICO files use embedded PNG data. The OS or browser picks the most appropriate resolution for each display context.
Which sizes should I include in my favicon?: For a standard web favicon, include at minimum 16px, 32px, and 48px. Modern browsers also use 64px and 128px for high-DPI displays. 256px is used by Windows for large icon views. The Minimal preset (16, 32, 48) is sufficient for most websites.
Does the tool support transparent backgrounds?: Yes. The image is drawn on a transparent HTML5 canvas and exported as PNG, preserving alpha transparency. Your ICO file will have a transparent background if your source image does.
What image formats can I convert?: Any image format the browser can display: PNG, JPG, WebP, GIF, SVG, and BMP. For favicon use, PNG with a transparent background is recommended.
Is my image uploaded to a server?: No. The entire conversion process: resizing, PNG encoding, and ICO assembly: happens in your browser using the Canvas API. Your image never leaves your device.
How do I use the generated .ico file?: Place favicon.ico at the root of your website (https://example.com/favicon.ico). Browsers will find it automatically. You can also reference it explicitly with: <link rel='icon' href='/favicon.ico' type='image/x-icon'>.
Can browsers display PNG favicons directly without ICO?: Yes. Modern browsers support PNG favicons referenced with <link rel='icon' type='image/png' href='/icon.png'>. An ICO file is still recommended for broad compatibility, particularly with older browsers and Windows system integrations.
Why does my icon look blurry at small sizes?: High-resolution images with fine detail do not scale down well. For small sizes (16px, 24px), consider using a simplified version of your logo: a single letter or bold symbol works better than a detailed illustration.
What is the difference between favicon.ico and apple-touch-icon?: favicon.ico is used by browsers for browser tabs and bookmarks. Apple Touch Icons (apple-touch-icon.png, typically 180px) are used by iOS when a user saves your site to their home screen. They are different files serving different purposes.

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