GIF is limited to 256 colors, and synonymous with short moving images. GIF opens in most environments, but another format such as ICO may suit some uses better.
ICO is a container format for favicons and Windows icons. When you convert GIF to ICO, it can be used as an icon or favicon. See the comparison below for what changes.
This converter reads the file itself to confirm it is GIF, then converts it to ICO right in your browser. Your image is never uploaded.
GIF vs ICO: what's the difference?
| Item | GIF | ICO |
|---|---|---|
| Compression | Lossless | Lossless |
| Transparent background | Yes | Yes |
| Animation | Yes | No |
| Introduced | 1987 | 1985 |
| Support in programs and upload forms | nearly everywhere | moderate |
| Shown directly in browsers | Yes | Yes |
| Photo file size (JPG = 1) | about 2.5× | n/a |
What is GIF?
GIF is one of the oldest web image formats, created in 1987, and can use only up to 256 colors per image. The compression itself is lossless, but reducing the colors to 256 makes photos look visibly coarse.
What is ICO?
ICO is the format used for Windows icons and website favicons. Its distinguishing feature is that one file can hold several sizes, such as 16×16, 32×32 and 256×256.
What changes when you convert GIF to ICO
Pixel values are preserved exactly
GIF and ICO are both lossless, so there is no change in quality. Only the file structure, compatibility and size differ.
Moving images keep only their first frame
ICO can't hold animation. If your GIF file is animated, only the first frame is converted.
It is fitted into a square of at most 256×256
ICO is limited to 256×256. Larger images are scaled down with their aspect ratio kept, and images that aren't square are centered with the leftover area left transparent.
ICO has no quality setting
ICO is lossless, so the quality slider doesn't apply. Instead, when converting from GIF you can manage file size by resizing (exact width and height, or a percentage).
How the file size changes
ICO holds images of up to 256×256, so a large original shrinks a lot. If the image is already small, the difference is negligible.
ICO has narrower support than GIF
GIF support is nearly everywhere and ICO support is moderate. Check that the recipient can open ICO first, and if you're not sure, JPG or PNG is safer.
When to convert
- You're making a website favicon or a Windows shortcut icon
- You're preparing an image for typical ICO uses (website favicons, windows program icons)
- You want to tidy a GIF file into a format that's easier to edit or archive