AVIF to ICO Converter

How to Convert AVIF to ICO Online

1. Upload Your AVIF File: Drag and drop or click "+ Add Files" to select one or more AVIF images. Batch conversion is supported, so a whole folder of brand assets can be processed in one pass.
2. Pick Image Quality and Compression: Under Image Compression, choose Quality Preset (default Very High), Target file size (%) for a percentage cap, Specific file size for an exact byte target, or Image Quality (%) for a 1-100 slider. Pair with Conversion Quality (72-1200 DPI) — 72 or 96 DPI is right for favicons; higher DPI only matters when the ICO will be used for desktop shortcuts on a 4K display.
3. Set Image Resolution (Optional): Pick a Preset from the dropdown (256P, 192P, 128P, 64P, 48P, 32P, 24P, 16P all map to standard favicon sizes), enter custom Width / Height in Pixels or Percent (Keep aspect ratio is on by default), or leave "Keep original" if your source is already at the target size. Under Image Transparency, leave "Unchanged" to preserve the AVIF alpha channel, or pick a flat background colour for legacy software that can't render transparent ICOs.
4. Convert and Download: Click Convert. Files process in your browser session — no sign-up, no watermark, originals are deleted from temporary storage after the job completes.

Why Convert AVIF to ICO?

AVIF (AV1 Image File Format) was published by the Alliance for Open Media in February 2019 and is now supported by Chrome 85+, Firefox 93+, Safari 16.4+, and Edge 121+ — roughly 94% of global browsers per caniuse. ICO is Microsoft's icon container from the Windows 3.x era and is what <link rel="icon"> falls back to when an SVG or PNG favicon isn't declared. Browsers don't render AVIF favicons, so any AVIF asset destined for the browser tab, taskbar, or RSS reader has to be transcoded — the AVIF is decoded to raw pixels and re-encoded as a PNG-in-ICO container (PNG-compressed images inside ICO have been supported since Windows Vista in 2007).

• Site favicon from a single hero image — A designer ships a 1024×1024 AVIF logo at 8-15 KB; converting to a multi-size ICO with 16×16, 32×32, and 48×48 yields one favicon.ico that covers every browser fallback path.
• Windows desktop shortcut icons — Right-click .exe or .lnk properties accept ICO only. AVIF source → 256×256 ICO is the maximum the ICO container natively addresses; anything larger has to be downsampled.
• GitHub repo favicon.ico — GitHub Pages and most static-site templates look for /favicon.ico at the root; a converted ICO drops in without code changes.
• Legacy CMS uploads — WordPress's classic Site Icon picker, Joomla, and older Drupal builds reject AVIF but accept ICO/PNG. Converting is the fast path when the CMS isn't on the upgrade roadmap.
• RSS readers and feed aggregators — Feedly and many self-hosted RSS apps still parse the ICO favicon over the <link rel="icon"> tag, so an ICO at the root keeps the feed icon working.
• Email signature icons in Outlook — Outlook's signature editor on Windows accepts ICO/PNG/JPG but not AVIF.

AVIF vs PNG vs WebP — Best Source Format for an ICO

When you already have an AVIF master, converting straight to ICO is fine; the visible quality difference between an AVIF-sourced and PNG-sourced 32×32 favicon is negligible because the bottleneck is the 1024-pixel budget, not the source codec. If the same logo is being shipped to both the browser as AVIF and to the favicon.ico slot, this is a single source of truth.

Favicon Size Cheat Sheet

The ICO container caps each slot at 256×256; sizes larger than that have to be referenced as separate PNG files in <link> tags. Need a different size as a standalone file? Use AVIF to PNG for the 180/192/512 PNGs, or PNG to ICO if your master is already a PNG.

Frequently Asked Questions

Why doesn't my browser just accept the AVIF as a favicon?

No major browser parses AVIF in the favicon decoder path as of mid-2026. Chrome, Firefox, and Safari all recognise SVG and PNG via <link rel="icon" type="image/svg+xml"> and image/png, but the image/avif MIME type isn't on the favicon allow-list. ICO (and PNG/SVG) is what the <link rel="icon"> tag falls back to, which is why the conversion is needed.

Does AVIF transparency carry over to the ICO?

Yes, when "Image Transparency" is left at "Unchanged". The AVIF alpha channel is decoded to 8-bit RGBA (ICO PNG slots store 8 bits per channel) and embedded as a PNG inside the ICO container. If you pick a named colour from the dropdown — White, Black, Navy, Crimson, etc. — the alpha is flattened against that background instead.

What's the largest icon size I can put in an ICO?

256×256 pixels per slot. That's a hard limit of the ICO container — the directory entry width/height fields are a single byte each, with 0 reserved to mean "256." For Apple Touch (180×180) or Android/PWA (192×192, 512×512) you ship separate PNG files referenced from the HTML head, not extra slots inside the ICO.

Should the source AVIF be at exactly 256×256?

Any size 256×256 or larger works — the converter will downsample to whatever you pick under Image Resolution (256P, 192P, 128P, 64P, 48P, 32P, 24P, 16P presets, or a custom Width/Height). Starting larger and downsampling produces sharper small icons than starting at 32×32 and upscaling.

Is the conversion lossless?

The AVIF→pixels step is lossless when the source AVIF was lossless; the pixels→PNG-in-ICO step is also lossless because PNG uses DEFLATE compression. If you pick Image Quality (%) below 100 or a Target file size that forces re-compression, the slot will use lossy encoding instead — for a 16×16 favicon this is usually invisible, but it can matter at 256×256.

Does the 10-bit AVIF colour depth survive?

No. ICO PNG slots are 8 bits per channel (24-bit colour + 8-bit alpha). A 10-bit AVIF gets quantised to 8-bit during conversion. For favicons this is a non-issue — at 32×32 there aren't enough pixels for banding to be visible — but it's a reason not to use ICO as an archival format for HDR source artwork.

Can I make a multi-size ICO that contains 16, 32, and 48 all in one file?

The XConvert tool produces a single-size ICO per conversion. For a multi-resolution favicon.ico containing 16×16, 32×32, and 48×48 together, convert the source three times at different presets and then combine the outputs with a multi-size ICO tool, or use a dedicated favicon generator. Most static-site generators and <link rel="icon" sizes="..."> declarations accept three separate .ico/.png files instead.

Will the converted ICO work as a Windows app icon?

Yes for the icon image itself — Visual Studio, NSIS, Inno Setup, and Electron's electron-builder all accept PNG-in-ICO files. For best results across legacy Windows (XP era) you'd also include BMP-encoded slots, which this converter doesn't do; for modern Windows 10/11 the PNG-only ICO is fine.

Are my AVIF files uploaded to a server?

Files are uploaded over HTTPS for processing and deleted from temporary storage after the job completes. There's no account requirement, no watermark, and no retention beyond the active session. If you'd rather keep the AVIF locally, the reverse direction is at ICO to PNG and from there to whatever destination you need.