Compress Image in KB Online
Compress your image and reduce its size to an exact target in KB, free and private. Upload a photo or signature, choose the KB limit you need, and download instantly. Nothing is uploaded — it all runs in your browser.
50% smaller
More options
Used for Make Smaller and Width & Height. Exact KB sets quality automatically.
Private
Image stays in your browser.
Fast
No upload required.
Free
No signup or watermark.
Flexible
Smaller, exact KB, or dimensions.
How to use
- 1
Upload your image
Drag in or select a JPG, PNG or WebP file.
- 2
Choose the KB target
Tap a size such as 50KB or 100KB, or enter a custom KB value.
- 3
Optionally resize
Reducing the dimensions in custom settings makes it easier to keep quality high.
- 4
Download
Compare original and compressed size, then download.
Compress images by exact KB
Compressing removes detail your eye barely registers — especially in smooth areas like skin and sky — to shrink a file dramatically. This tool lets you compress to an exact target in KB, so you hit a form's limit precisely instead of guessing.
Smart two-stage compression
First the tool finds the best JPG quality that fits your KB target using a binary search. If a very large image still will not fit, it scales the dimensions down in steps and tries again. The result: small images keep full resolution, and large ones are reduced gently rather than turned into a blocky mess.
No uploads, ever
This compressor runs entirely in your browser using the Canvas API — no server, no storage, no tracking of your image. That makes it ideal for sensitive documents and ID photos. Want to set an exact KB number quickly? Try the resize image in KB tool.
Frequently asked questions
How do I compress an image to a specific KB?
Upload the image, set the target file size in KB, and the tool searches for the JPG quality that lands at or just under it. You end up slightly below the limit, which is what "maximum" rules want.
How can I reduce image size in KB without losing quality?
The tool always keeps the highest quality that fits your target. To preserve even more, reduce the pixel dimensions to what you actually need — fewer pixels means each one stays higher quality at the same KB.
Is there a limit on how many images I can compress?
No. Because everything runs in your browser with nothing uploaded, you can compress as many images as you like for free.
Are my photos uploaded to a server?
No. Every step — resizing, cropping and compression — happens locally in your browser using the HTML5 Canvas API. Your image never leaves your device, and nothing is stored or transmitted.
What should I do if my image cannot be compressed enough?
Open the "Need exact width, height or quality?" section and reduce the width and height — a smaller image reaches a tiny KB target far more easily. Make sure the output format is JPG, and start from the original photo rather than a screenshot. If a target is physically impossible, the tool shows the smallest clear result it can make instead of a broken file.
Which output format should I choose?
Choose JPG for photographs and most form uploads because it gives the smallest file size. Use PNG only when you need a transparent background or razor-sharp line art. WebP gives excellent compression but some older government portals do not accept it — check the form requirements first.
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