Favicon compressor & .ico optimizer
Shrink a bloated favicon.ico, or turn a PNG or SVG into a compact
one. It re-encodes each icon as a PNG inside the .ico instead of
the uncompressed bitmap most tools emit. Usually a two-thirds size cut.
Your image never leaves your device. There is no upload and no server. Everything runs in your browser.
Choose an image
.ico Inside your .ico
The images it contains, and how each one is encoded. Read on your device, not uploaded.
| Size | Encoding | Bytes |
|---|
Preview
How the icon renders at each size. Save any one as a PNG.
HTML to include
How it works
An .ico is a small container: a header, one directory entry per
image, then the image data. Each image is stored either as a raw
BMP/DIB bitmap or, since Windows
Vista, as a whole PNG. Most tools still write the 16, 32 and 48px images as
uncompressed 32-bit bitmaps, which is why a plain favicon can
weigh 15 KB.
This tool re-encodes each size as an indexed-colour PNG and repacks the
.ico, picking the smallest palette that stays visually lossless,
usually a two-thirds cut. Drop an existing .ico and it also shows
how the current file is built, so the saving is visible rather than a claim.
For a modern site you can go further and ship an SVG favicon
(a few hundred bytes, crisp at any density) with the .ico kept only
as a fallback for older browsers.
A free tool by Kriyak, freelance software development.
Questions
- Why is my favicon.ico so large?
- Most editors and converters store the 16, 32 and 48px images as uncompressed 32-bit BMP bitmaps, the pre-Vista code path they still default to. PNG inside an .ico has been valid since Windows Vista and is far smaller, so switching the encoding shrinks the file without changing how it looks.
- How do I make a favicon.ico smaller?
- Drop your .ico, or a PNG or SVG of your logo, above. It re-encodes each size as an indexed-colour PNG inside the .ico, usually a few times smaller, and gives you the file back.
- What should I use for the sharpest result?
- A square SVG, or a PNG of 256px or larger. Smaller or non-square sources still work, they just scale up less cleanly. You can also drop an existing .ico to recompress it in place.
- Which favicon sizes do I need?
- 16 and 32px cover browser tabs and bookmarks; 48px covers a few Windows surfaces. Those three in one .ico are plenty. A modern site can also ship an SVG favicon and keep the .ico for older browsers.
- Does it work with SVG and PNG, not just .ico?
- Yes. SVG, PNG, JPEG, WebP and GIF all work as input. It rasterises the sizes you pick and packs them into an .ico.
Need a tool like this, or something else built? See what I do or get in touch.