ICO to AVIF Converter
To convert ICO to AVIF, add your ICO file, choose AVIF and press Convert. The largest image inside the icon is encoded as AVIF, starting at 60% quality, and transparent areas are kept. Expect a small picture, since icons rarely exceed 256 pixels. AVIF is newer than most formats and some older apps cannot open it. The conversion runs in your browser, so the icon stays on your device.
- Free, no sign-up
- Your file never leaves your device
- Up to 50 MB per file
Your file never leaves your device; images are processed in your browser. EXIF and location data are not added to the output.
How to convert ICO to AVIF
Add your ICO files
Drag the images onto the upload area or browse for them; you can add several files at once.
Keep AVIF as the output
AVIF is already selected. For formats with a quality setting the slider starts at a default that suits the format (JPG 90%, WebP 80%, AVIF 60%); lower it if you want a smaller file.
Convert and download
Press “Convert”. Every file is processed in your browser, and you can download the results one by one or as a ZIP.
What is preserved?
Kept
- The image resolution (pixel dimensions)
- The correct photo orientation (EXIF orientation is applied)
- Colors (adapted to sRGB)
- Transparency (alpha channel)
Changed
- AVIF is a lossy format: lower quality means a smaller file but less fine detail
- The lossless source is recompressed at the quality you choose, so pixel values are no longer identical
- Only the largest size inside a multi-size ICO file is used
Not carried over
- EXIF, location and camera data: left out of the output for privacy
When to use it
Lightweight icons for a web app
A web app that already uses AVIF for its images can convert legacy ICO assets to the same format and serve them consistently.
Store an icon collection compactly
Large collections of Windows icons take less space as AVIF, while keeping the transparent backgrounds for preview galleries.
Limitations to know
- Up to 50 MB per file; the output can be at most 16,384 pixels on one side.
- On iPhone and iPad, images above roughly 16 megapixels may not be processed because of a browser limit.
About the formats
What is ICO?
ICO is an icon format that stores several square sizes (for example 16, 32 and 48 pixels) in a single file. It is used for Windows icons and for a website's favicon.ico; when a browser needs a small tab icon it picks the matching size from the file. It supports transparency, but cannot be larger than 256 × 256 pixels.
What is AVIF?
AVIF is a modern image format based on the AV1 video codec. It delivers very small files at high visual quality, supports transparency, HDR and animation, and is among the most efficient formats for the web. Encoding is slower than for other formats, and some older software cannot open AVIF yet.
Frequently asked questions
Is AVIF worth it for tiny icons?
The saving is small in absolute terms because icons are already only a few kilobytes. It makes sense when your whole site uses AVIF; otherwise PNG is simpler and lossless.
Will the 60% default blur my icon?
On small icons with sharp outlines it can soften edges. Raise the quality to 85% or more for icons; the file grows only slightly.
Which icon size ends up in the AVIF?
The largest one stored in the ICO. Smaller versions are ignored because they hold less detail.
Is converting ICO to AVIF free?
Yes, completely free. There is no account, subscription or watermark; just add your files and convert them.
Are my files uploaded anywhere?
No. Images are processed in your browser and never leave your device, so the waiting time depends on the file size and your device. EXIF and location data are not added to the output.