Image Resizer
Drop in a JPG, PNG or WebP image, set new dimensions — by pixels or by percentage — pick an output format and quality, then download the result. The image is decoded and redrawn entirely on this page; it is never uploaded anywhere.
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Runs entirely in your browser using the HTML5 Canvas API — the file you drop is never uploaded or sent to a server. Reloading or closing this page discards it; nothing is stored anywhere on our end.
How the resize works
Your image is decoded into memory and drawn onto an off-screen canvas sized to the width and height you choose, using the browser's own scaling — the same operation any image-editing app performs, just running locally in JavaScript instead of on a server. Locking the aspect ratio keeps width and height in the same proportion as the original as you type; the percentage field is a shortcut that sets both from the original dimensions in one go. Enlarging an image stretches its existing pixels rather than inventing new detail, so results are sharpest at or below the original size. The canvas is then exported in the format and quality you picked, and a download link is built from that exported file — again, all on this page.
- Is my image uploaded anywhere?
- No. The file you drop or browse to is read and redrawn using your browser's built-in Canvas API, and the download link is generated from that in-browser result. No network request is made with your image data — everything above happens on this page, in this tab, even if you disconnect from the internet after it loads.
- Which output format should I pick?
- PNG is lossless and keeps transparency, so it's the right choice for logos, screenshots or graphics with sharp edges or text, at the cost of a larger file. JPEG and WebP are lossy and compress much smaller using the quality slider — good for photos — but JPEG has no transparency (any transparent area is filled white on export), while WebP does support transparency. If your browser can't encode WebP, the download falls back to PNG automatically and the result note says so.
- Why does my resized image look soft or blocky?
- Shrinking an image generally keeps it looking sharp because there's more original detail than the output needs. Enlarging it beyond its original pixel dimensions has to invent pixels by stretching what's there, so it looks softer the further past 100% you go — resizing can't add detail a photo never captured. Blockiness instead of softness usually means the quality slider is set low for a JPEG or WebP output; raise it for a cleaner result at the cost of a larger file.
FAQ
Sources
Method: this tool makes no factual or legal claims to source — it's arithmetic and browser APIs. The dropped file is loaded into an <img> element, drawn onto an off-screen <canvas> at the target width and height with the browser's own image scaling, then exported with canvas.toBlob() (falling back to canvas.toDataURL() in browsers that lack it) in the chosen format and, for JPEG and WebP, the chosen quality. Width/height locking and the percentage field are simple ratio arithmetic against the image's original pixel dimensions.