Compress any image to an exact file size — 50 KB, 100 KB, 200 KB or a custom target. Free, and it runs entirely in your browser, so photos are never uploaded. No account, no watermark, no limits.
Select an image and choose your target file size
Our algorithm compresses images to match your target size exactly using binary search optimization.
All processing happens in your browser. Your images never leave your device.
Client-side processing means instant results with no upload time. Completely free to use.
Compress an image to KB when you need to hit an exact file size like 50 KB, 100 KB, or 200 KB, not just "smaller." This tool lets you set a precise target file size in kilobytes and it iterates the compression until the output lands at or under that limit, so your JPG or PNG fits a strict upload cap without guesswork. Everything runs entirely in your browser using WebAssembly and Canvas, meaning your image is never uploaded to a server, and the tool works offline once the page has loaded.
Most compressors only give you a quality slider and let you guess how small the result will be. Compressing to an exact KB target flips that around: you name the file size you must not exceed, and the tool works out the quality and encoding needed to meet it. This matters because government portals, job boards, exam registration sites, and banking forms almost always specify a hard limit such as "photo must be under 100 KB" or "between 20 KB and 50 KB."
Behind the scenes, hitting an exact size is a search problem. The tool re-encodes the image at progressively lower quality levels and measures the resulting bytes each time, converging on the highest quality that still fits your KB budget. Because this happens locally in your browser, the trial-and-error is instant and private, with no round trips to a server.
Strict KB limits show up far more often than most people expect, and "close enough" gets your form rejected. Compressing to a precise target removes the back-and-forth of exporting, checking the size, and exporting again.
File size is driven mostly by three things: pixel dimensions, the encoding quality, and the format. To reach a small KB target while keeping the image usable, the tool prioritizes lowering quality first and, when necessary, reducing dimensions, rather than crushing a huge image into a tiny box in one step.
The tradeoff is real but manageable. A photo compressed to 50 KB will show more artifacts than the same photo at 500 KB, but for a passport-style headshot or a form thumbnail the difference is usually invisible at the size it will actually be viewed. The key is starting from an image that is no larger in dimensions than it needs to be, so the encoder spends its byte budget on detail you can see rather than pixels no one will.
For photographs and images with lots of color gradients, JPEG reaches small targets most efficiently because it uses lossy compression tuned for natural images. For graphics with flat color, sharp edges, or text (logos, screenshots, icons), PNG preserves clarity but is harder to shrink to very small sizes; if a portal accepts it, WebP often beats both, hitting the same visual quality at a noticeably smaller file size.
A few habits make a strict KB limit painless.
Because every step happens client-side in your browser, your image never leaves your device. There is no upload, no server-side copy, and no account to create. That makes it safe for sensitive documents like ID photos, signatures, and scanned paperwork, and it means the tool keeps working even if your connection drops after the page has loaded. It's free with no watermark and no daily limit.
Set the target to 100 KB and load your JPG; the tool automatically lowers the encoding quality until the file fits under 100 KB while keeping quality as high as possible. If a photo won't reach 100 KB at acceptable quality, reduce its pixel dimensions first, since a smaller image reaches small targets far more cleanly.
Yes. Enter 50 or 20 in the target field and the tool converges on the highest quality that stays at or under that size. Very small targets like 20 KB work best on smaller or cropped images, since forcing a large photo that low introduces visible artifacts.
Reaching a smaller file size does involve some quality loss because the tool uses lossy compression to hit tight KB budgets. For form photos, thumbnails, and web images viewed at normal size the loss is usually unnoticeable; the smaller your target relative to the image's detail, the more visible artifacts become.
JPEG is best for photos and reaches small KB targets most efficiently, while PNG is better for logos, screenshots, and text-based graphics. If the site you're uploading to accepts WebP, it typically hits the same quality at a smaller size than either.
Portals cap file size to control storage, speed up uploads, and keep their systems responsive under heavy load. Passport, visa, exam, and job application forms are the most common places you'll see hard limits like 20-100 KB for photos and signatures.
No. All compression happens inside your browser using WebAssembly and Canvas, so the image never leaves your device and no server ever receives it. This makes it safe for ID photos, signatures, and other sensitive documents.
No account and no payment are required. The tool is completely free with no watermark and no daily limits, and it keeps working offline once the page has loaded.
If an image can't hit a very small target at acceptable quality, reduce its dimensions or crop it before compressing. Fewer pixels means the encoder can spend its byte budget on the detail that matters, letting you reach targets like 30 KB without the result looking broken.
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