What is ICO format and why convert AVIF to ICO?

ICO (Icon) is the file format used by Windows for application icons and browser favicons. It stores one or more images at different sizes in a single file. Converting an AVIF to ICO lets you use a next-gen AVIF image as a desktop icon, taskbar icon, or website favicon.

Can I crop the AVIF image before converting to ICO?

Yes — the tool provides an interactive crop overlay on the source image. Drag the corner and edge handles to define exactly which portion of the AVIF you want in the output ICO. Click Preview Crop to see the result before downloading.

Does my image get uploaded to a server?

No. All processing — loading, cropping, and ICO encoding — happens entirely in your browser using JavaScript and the HTML5 Canvas API. Your image never leaves your device.

What sizes does the output ICO file contain?

The output ICO embeds your cropped image as a PNG at the exact pixel dimensions of your crop selection. Modern ICO files support embedded PNG data, compatible with Windows Vista and later, as well as all major browsers for favicon use.

Why use createImageBitmap for AVIF loading?

AVIF uses AV1 compression that requires asynchronous GPU-accelerated decoding. The browser's Image element fires onload before AV1 pixel decoding completes, which silently produces a blank canvas. createImageBitmap() resolves only after the full pixel decode is ready, ensuring a correct result every time.

How do I reset and convert a different image?

Click the Start Over button that appears after loading an image. This clears the current file and resets the crop area so you can load a new AVIF.

AVIF to ICO Crop Converter

Load an AVIF image, drag the crop handles to define exactly the area you need, preview the result, then download an ICO icon file. Everything runs in your browser — your image never leaves your device.

🖼️

Drop an AVIF here

or Browse Files · AVIF supported

What This Tool Does

This tool loads an AVIF image directly in your browser, presents an interactive crop overlay with draggable handles, and converts the selected area to an ICO file. No server upload is required. The full workflow — loading, cropping, encoding — runs entirely in client-side JavaScript using the HTML5 Canvas API. AVIF files use AV1 compression that requires full pixel decoding before the canvas can draw them; this tool uses createImageBitmap() to guarantee the decode is complete before drawing, preventing the silent blank-canvas problem that affects standard Image element loading with AVIF. The output is an ICO file with an embedded PNG image, compatible with Windows Vista and later, all major browsers for favicon use, and any icon-aware application.

Who This Is For

Web developers who have AVIF source artwork and need a cropped favicon in ICO format
Designers preparing Windows application icons from next-gen AVIF source files
Anyone converting a specific region of an AVIF photo to an icon without installing software
Developers who need a quick crop-and-convert workflow that stays entirely in the browser

AVIF vs ICO: Format Comparison

Property	AVIF	ICO
Primary use	Web images, photos	Application icons, favicons
Compression	Lossy or lossless (AV1)	PNG or BMP embedded (varies)
Transparency support	Yes (alpha channel)	Yes (32-bit RGBA)
Multiple sizes in one file	No	Yes — standard for icons
Browser favicon support	Limited (not universal)	Universal — every browser
Windows icon support	No	Yes — native
Typical file size	Very small (best compression)	Small (PNG-embedded)
Best for	Web delivery, high-quality photos	Favicons, Windows icons, app icons

Frequently Asked Questions

Why does this tool use createImageBitmap instead of the standard Image element?▼

AVIF uses AV1 video codec compression that requires asynchronous GPU-accelerated decoding. When you load an AVIF with new Image() and FileReader.readAsDataURL(), the browser fires the onload event before the AV1 pixel decoding completes. Calling ctx.drawImage() at that point silently draws a blank canvas — no error, no warning, just empty output. createImageBitmap(file) is a Promise that resolves only after the full pixel decode is ready, so the canvas always receives real pixel data.

How precise is the crop tool?▼

The crop operates at native pixel accuracy on the original AVIF dimensions. The canvas is scaled to fit your screen for display, but the actual crop coordinates are mapped back to the full-resolution image before the ICO is generated. You get an ICO at the exact pixel dimensions shown in the crop dimensions badge.

Should I crop to a square for favicon use?▼

Yes — browser favicons and Windows icons are always displayed square. If your crop selection is not square, the ICO will contain a non-square image that most icon renderers will stretch or letterbox. Use the crop dimensions badge to confirm equal width and height before downloading.

What browsers support AVIF?▼

AVIF is supported in Chrome 85+, Firefox 93+, Edge 121+, and Safari 16+. Older browsers do not support AVIF. If your source file does not load, verify your browser is up to date. The tool checks for createImageBitmap support automatically.

Is there a file size limit?▼

There is no server-imposed limit because no upload occurs. The practical limit is your browser's available RAM. Most modern desktops handle AVIF files comfortably. Very large files on memory-constrained mobile devices may be slower to process.

What is the maximum recommended ICO output size?▼

For favicons, 16×16, 32×32, and 48×48 pixels are standard. For Windows application icons, 256×256 is the maximum size supported natively. The ICO format can technically store larger images, but standard use cases stay at 256×256 or smaller.

AVIF to ICO Crop Converter

What This Tool Does

Who This Is For

AVIF vs ICO: Format Comparison

Frequently Asked Questions

Explore More Tools

Learn More