UsefulTab
Resize Image to KB
Compress an image to an exact target size in KB.
Add an image to hit a KB target
Add a JPG, PNG, or WebP image, pick a target like 50 KB, then Resize. The tool compresses it to land at or under your limit and shows the final size — all in your browser, nothing uploaded.
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Compress an image to an exact size in KB
ResizeImageToKB shrinks a JPG, PNG, or WebP image until its file size is at or below a limit you set in kilobytes — handy for exam portals, visa and job application forms, and any upload with a strict size cap like 20 KB, 50 KB, or 100 KB. It binary-searches the encoder quality to land just under your target, and if even the lowest quality is still too big it automatically scales the dimensions down and tries again, so it can hit aggressive limits that a plain quality slider cannot. Everything runs on your own device — the image is never uploaded to a server.
Common questions
How do I compress an image to exactly 50 KB?
Add your image, click the 50 KB preset (or type any number in the target field), then click Resize. The tool searches the encoder quality to produce the largest file that still fits at or under 50 KB, and shows the final size so you can confirm it meets the limit.
What if my target is very small, like 20 KB?
If even the lowest JPEG/WebP quality is still over your target, the tool automatically reduces the image's pixel dimensions step by step and re-encodes until it fits. Very small targets on a large photo will therefore come out at reduced resolution — that is the only way to reach the limit.
Why can't I hit the target with PNG?
PNG is lossless, so its size cannot be dialled to an arbitrary KB value. For a strict size limit choose JPEG (best for photos) or WebP (smallest) — the tool defaults to JPEG, which is what most portals accept.
Does the result go slightly under or over the target?
The tool always aims for at or under your limit, never over, since portals reject files that exceed the cap. It gets as close to the limit as it can from below so you keep the most quality possible.
Is my image uploaded anywhere?
No. The image is decoded, re-encoded, and measured entirely in your browser with the Canvas API. Nothing is sent to a server, so it also works offline once the page has loaded.