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JPG to ICO Converter

JPG is universal, but it is lossy and cannot store transparency. Converting to Windows ICO icons gives you the icon format browsers look for at /favicon.ico and Windows uses for shortcuts. Two limits push people off JPEG: it has no alpha channel at all, so there is no way to store a transparent background, and every re-save discards more detail. That second one accumulates — an image edited and re-saved a dozen times looks visibly worse than the original with no single step to blame. Website favicons and Windows shortcut icons — a square source with clear shapes that still read at 16 pixels. Drop your files below and the work happens on your own machine: the conversion runs in the browser through the Canvas API, so nothing is uploaded, there is no file-size cap, no watermark and no sign-up. Batches are fine — drop a folder's worth and take them back as a single ZIP.

Drop images here

or click to browse — JPG, PNG, WebP, HEIC, AVIF, GIF, BMP, SVG

Private: files never leave your device

What a JPG file actually is

JPEG has been the default photographic format since 1992. It divides the image into 8×8 blocks and discards the high-frequency detail within each one, which is why it compresses photographs so well and why hard edges and flat colour — screenshots, logos, text — pick up the smeared halos known as ringing artifacts.

Almost every camera, scanner and non-Apple phone writes JPG, and it is what a website will hand you when you save an image. If a file came from somewhere and you have no idea what produced it, JPG is the safe bet.

What you get from ICO

ICO is a container that holds one or more small square images, with transparency, for use as an icon. It caps out at 256×256 — anything larger has to be scaled down, and the format is not intended for general pictures.

Every browser requests /favicon.ico by default, with no HTML required, and Windows uses ICO for application and shortcut icons. It is a narrow format that is completely reliable inside its niche.

What changes when you convert JPG to ICO

An icon is being built here, not a picture converted. The JPG is decoded, scaled to fit within 256×256 and stored losslessly inside the ICO container — so whatever compression artifacts the original carried are preserved faithfully, then shrunk to the point where nobody will ever see them. Detail is lost to the scaling, which is the intended outcome.

There is no transparency to preserve — JPG files do not carry an alpha channel, so every pixel is opaque to begin with. Converting to a format that supports transparency does not create any; it only means you could add it later in an editor.

ICO cannot exceed 256×256, so anything larger is scaled down to fit while keeping its aspect ratio. Work from a square source if you can — a wide image gets letterboxed into the square, and fine detail disappears entirely at the 16-pixel size a browser tab actually renders.

A JPEG is an awkward icon source because it cannot carry transparency, so the icon arrives with whatever background the photo had, as a solid square. For a logo on white that is often fine; for anything meant to sit on a coloured toolbar it is not, and the background needs removing first.

Frequently asked questions

Is this JPG to ICO converter really free and private?

Yes. Conversion happens entirely in your browser using the Canvas API — your JPEG photographs are never uploaded to a server, there is no file limit, no watermark and no sign-up.

Can I convert multiple JPG files at once?

Yes — drop any number of files and they convert in one batch. Use "Download all" to save the results as a single ZIP.

What size will my ICO file be?

ICO cannot store an image larger than 256×256, so anything bigger is scaled down to fit while keeping its aspect ratio. For a browser favicon a square source works best — 256×256 covers every modern use, and browsers scale it down to the 16 or 32 pixel tab icon themselves.

How do I use this as my website favicon?

Save the file as favicon.ico in your site's root directory. Browsers request /favicon.ico automatically, so no HTML is strictly needed — though adding <link rel="icon" href="/favicon.ico"> makes it explicit.

Does converting JPG to ICO lose quality?

An icon is being built here, not a picture converted. The JPG is decoded, scaled to fit within 256×256 and stored losslessly inside the ICO container — so whatever compression artifacts the original carried are preserved faithfully, then shrunk to the point where nobody will ever see them. Detail is lost to the scaling, which is the intended outcome.

Should the icon be square?

Yes. ICO holds square images, so a wide or tall source is fitted into the square and ends up with empty space around it. Start from a square design with generous margins — the tab icon renders at 16 pixels, where anything intricate turns to mush.

I converted a JPG and re-saved it a few times — why does it look worse?

Every JPEG save re-runs the lossy compression, and the damage accumulates across generations. The fix is to keep one original and always export from it, rather than editing and re-saving the same JPG repeatedly.

Related conversions

JPG → PNGJPG → WebPPNG → ICOWebP → ICOHEIC → ICOAVIF → ICO

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