Resize Image to a Target File Size
Resize and compress until your image fits a KB target — smart search over dimensions and quality finds the best fit at or under your limit.
About the Resize to KB
Unlike pure compression, this tool walks dimensions down too — so a 4000×3000 original can land at or under 200KB while still using the highest quality that fits. If the target is unreachable for a particular file, it says so rather than exceeding your limit. Ideal when upload forms check size and you want maximum resolution under that limit.
How it works
This tool outsmarts simple compression by searching two dials at once: it progressively trims the longest edge (up to your max-dimension cap) and re-encodes at descending quality until the file lands at or under your KB target. The result keeps as many pixels as the size budget permits.
How to use it
Drop up to 10 images, type the target size in kilobytes, optionally cap the max dimension so the search prefers scaling, choose JPG or WebP, and run. Each result confirms the achieved size — download or re-run with a different cap.
Supported formats & limitations
Accepts .jpg, .png and .webp up to 30MB each; output is JPG or WebP. Very small targets (under ~30KB) eventually cost real resolution — that's physics, not the tool. Setting a sensible max dimension yields visibly better results.
Common use cases
When a portal says 'maximum 150KB' and you also care how the photo looks, this beats a plain compressor. Common at university admission portals, tender submissions, marketplace listings and anywhere both size and dignity matter.
Frequently asked questions
How private is Resize to KB?
Everything runs locally in your browser via the Canvas API. Your picture never leaves your machine — there is no upload step at all, so processing is as private as working in an offline editor.
Can it open JPG, PNG and WebP files?
The common formats are covered — JPG, PNG or WEBP, each up to 30 MB. Queue them one batch at a time.
How many images can I process at once?
Batch runs take up to 10 files at once (30 MB each). There's no account, no daily quota and no watermark — process as many batches as you need.
Can I fine-tune the result before downloading?
You can adjust Target size (KB), Optional max dimension, Output format. Results are previewed after processing, so tweak values and re-run until the output looks right.
Why did the tool shrink the dimensions instead of only lowering quality?
The tool searches both dimensions and JPEG/WebP quality to hit your KB target. If quality reduction alone can't reach the target without ruining the image, it reduces the longest edge as well — that's usually the better trade-off for form uploads.
What KB target should I choose for online forms?
Most exam, visa and job-application forms accept photos between 20 KB and 100 KB and signatures between 10 KB and 20 KB. Check the exact limit on your form, then enter that number as the target — the tool finds the closest possible fit.
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