Will my favicon have a transparent background?

No. A JPG stores no transparency, so the icon carries whatever background the image had, usually a coloured rectangle. It'll look like a filled square in the tab. For transparency you need to start from a PNG or an SVG.

Which sizes are included?

16, 32, 48 and 256 pixels inside the same file. The first two are the browser tab, 48 is shortcuts, and 256 covers Windows Explorer and high-density screens.

What if my JPG isn't square?

ICO entries are always square. If the image isn't, it gets centred and padded rather than cropped, so you'll end up with bands at the sides. Crop it to square yourself first and you control which part survives.

Will a photo work as a favicon?

Almost never. At 16 pixels a photograph turns into a smudge of colour with no recognisable shape. Favicons that work are simple, high-contrast symbols, not detailed images.

How big should the JPG be?

At least 256 × 256 pixels. Every entry is produced by scaling down, and scaling down preserves detail while scaling up invents it.

Convert JPG to ICO

Drop the JPG and download an ICO with every size a favicon needs.

Drop an image here

or pick a file

PNG, JPG, WEBP, HEIC, AVIF, JXL, GIF, BMP, TIFF and SVG · up to 20 MB

A JPG can be a favicon, with one caveat

An ICO can be made from a JPG with no technical trouble: the file comes out correct, with its four resolutions inside, ready to upload as favicon.ico. But it's worth knowing what you're getting into, because there's one limitation that comes from the source format and can't be worked around.

JPG stores no transparency

That's the important caveat. Your favicon will carry whatever background the original image had, and a JPG always has one: if the logo sat on white, the icon will be a white square with the logo inside it.

In a browser tab that shows. Favicons that look right float on the tab's own background, light or dark; one with a white box around it shouts on a dark theme and reads like a badly cut sticker.

If you have the logo as a PNG with a transparent background or, better still, as an SVG, use those as the source. The result is in a different league, and with SVG each size is drawn from the vector rather than shrunk from an image.

And if it's a photograph, almost certainly not

A photograph doesn't fit in 16 × 16 pixels. Any image with detail turns into a patch of colour where nothing is recognisable. A favicon works for the same reasons a road sign does: one simple shape, high contrast, no text.

If what you have is a photo, what you need isn't a conversion but a symbol: the brand's initial, a simple icon, a recognisable shape. That gets designed, not converted.

Crop to square before converting

ICO entries are square. If your JPG is rectangular it gets centred and padded here, and the bands at the sides make the artwork look smaller than it needs to. Cropping it yourself to the square you want gives a far better result, and the crop tool does exactly that.

Why it weighs more than you expected

An ICO stores each resolution separately, sharing nothing between them, so the file ends up being the sum of all of them. Four come out by default — 16, 32, 48 and 256 — and the 256 one takes almost all of it: starting from a 192 × 192 image, all four together come to around 97 kB and the first three to 10 kB.

If the icon is for the browser tab, 16,32,48 in the sizes field is plenty and the file drops by 90%. The 256 entry only earns its place when the icon is shown large, as in Windows Explorer.

How much it weighs, measured

Not an estimate. It's this same conversion run on our server, with the quality settings applied when you do it yourself.

Source file	JPG	10 kB
Result	ICO	96 kB
Difference		×9.2

Measured in August 2026 on a 192×192 logo. Your image will give a different figure, since it depends on what's in it, but the ratio will look similar.

Common questions

Will my favicon have a transparent background?: No. A JPG stores no transparency, so the icon carries whatever background the image had, usually a coloured rectangle. It'll look like a filled square in the tab. For transparency you need to start from a PNG or an SVG.
Which sizes are included?: 16, 32, 48 and 256 pixels inside the same file. The first two are the browser tab, 48 is shortcuts, and 256 covers Windows Explorer and high-density screens.
What if my JPG isn't square?: ICO entries are always square. If the image isn't, it gets centred and padded rather than cropped, so you'll end up with bands at the sides. Crop it to square yourself first and you control which part survives.
Will a photo work as a favicon?: Almost never. At 16 pixels a photograph turns into a smudge of colour with no recognisable shape. Favicons that work are simple, high-contrast symbols, not detailed images.
How big should the JPG be?: At least 256 × 256 pixels. Every entry is produced by scaling down, and scaling down preserves detail while scaling up invents it.