1Upload the ICO icons you want resized — work from the largest original you have rather than from a copy you already shrank once.
2Type a target width, a target height or a percentage, and leave the aspect-ratio lock on unless you deliberately want stretching.
3Run the resize; every file in the batch is taken to the same target in a single pass.
4Download the resized ICO file, or the whole set together as one archive.
Resize ICO FAQ
Does the source format affect the result of a resize?
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It does. ICO is a container that holds several square bitmaps at once (16, 32, 48, 64, 128 and 256 px) so Windows and browsers can pick the size they need. That is what decides whether shrinking the file is purely a question of pixels or also a question of re-encoding.
Is there anything specific to ICO I should watch for?
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Yes — an ICO is a stack of square bitmaps, not one image, so operations apply to the stack and Windows still picks whichever size it wants. Worth checking before you resize a file you will not be able to regenerate.
How does Resize ICO change the dimensions?
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Concretely, the request is really about which sizes belong in the stack: entries are re-rendered at the standard 16, 32, 48, 64, 128 and 256 pixel steps rather than at an arbitrary dimension, because that is what Windows and browsers ask for. You give it a target width, a target height or a percentage, and it works from the original rather than from a previously resized copy.
Can I keep the aspect ratio, or force exact dimensions?
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Both. Lock the ratio and one dimension is derived from the other, which is what you want almost always. Unlock it and you get exactly the numbers you typed, at the cost of stretching — useful for a fixed slot, wrong for a photograph.
Which sizes should the icon contain?
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16, 32 and 48 pixels cover Windows Explorer and browser tabs; 256 covers large-icon view and modern shortcuts. Keeping all of them in one file costs almost nothing and stops the operating system from having to guess.
What can I upload to Resize ICO?
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ICO files containing one or several sizes, plus ordinary PNG or JPG artwork if you are building an icon rather than editing one. Windows .ico and browser favicon files are the same format.
Is there a file size limit on Resize ICO?
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Yes: free accounts process images up to 25 MB each, which no icon file will ever approach — a full 16-to-256-pixel stack is typically well under 200 KB. Icons are the one part of the image family where the cap is genuinely irrelevant.
Will Resize ICO lower the quality of my ICO icons?
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The sizes stored inside an ICO are lossless bitmaps, so the pixels themselves do not degrade. What actually decides how good an icon looks is whether the size the operating system asks for exists in the stack — a 256 px entry downscaled on the fly by Windows always looks worse than a real 32 px entry.
Why would a modern-format site run Resize ICO?
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WEBP.to is built around the modern replacement for both of the old defaults: one format that does lossy, lossless, alpha and animation, and reliably lands smaller than the JPEG or PNG it came from. People arrive here having decided the old defaults are costing them bandwidth, and that decision immediately raises the rest: what size, what quality, what happens to the transparency. Resize ICO is on the same upload and the same account so those questions get answered in one place.
Once Resize ICO has run, what is worth doing next?
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The converter on this site moves images to and from WebP, PNG, JPG and AVIF, which is where you decide whether a smaller file is worth losing the older browsers. Doing it in that order matters: pick the pixels first and the container afterwards, because the container is the cheap decision and the pixels are the expensive one.
Do the sibling sites run something different?
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The engines are identical — same libraries, same workers, same caps. What is different is the opinion attached, and the opinion here rests on a property of the format this site is named after: the same .webp extension can hold a lossy VP8 frame, a lossless one, or an animation, so the sensible processing path is decided per file rather than per extension.
What happens to my file, and is an account required?
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No account, and nothing is retained: uploads are deleted from the workers shortly after the job finishes, and nothing is inspected, listed or indexed. Accounts exist for history and batch size only.
