Reduce Image to Exact KB

Need a photo under 500KB for a form? 200KB for an email? Type the number, done.

No uploadBinary searchJPG/WebP output
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Drop your image here

JPG, PNG, WebP. Output will be JPEG (PNG can't target KB reliably).

How to reduce an image to a specific KB size

1

Drop your image

Drag in any JPG or PNG. The file loads locally — nothing is sent to a server.

2

Enter target size in KB

Type the number you need — 100, 200, 500, whatever the form or upload limit requires.

3

Hit Reduce

The tool uses binary search to find the right quality setting that hits your target size.

4

Download

Check the file size matches, then save it. The dimensions are untouched.

Why you need a target KB tool, not just a quality slider

Most image compressors give you a quality slider and let you figure out the rest. That works fine when you just want the file to be smaller. But when you have a hard limit — a government form that rejects uploads over 200KB, an email system with a 500KB attachment cap, a job application portal that will not accept anything larger — guessing at quality settings is frustrating.

This tool takes a different approach. You tell it the target size in KB, and it runs a binary search through quality settings until it finds one that gets the file under your limit. Compress, check size, compress more or less, check again. It does all of that automatically.

The result is not always pixel-perfect to your exact number — compression does not work that way — but it gets you within a few percent of the target, which is usually close enough.

Also useful

Compress ImageConvert ImageResize Image

FAQ

How accurate is the size reduction?+
Usually within 5-10% of your target. The binary search approach gets close but image compression is not perfectly linear, so there can be a small gap.
What is the minimum size I can hit?+
It depends on the image content. Very compressed images hit a floor where further quality reduction produces almost no size benefit. A complex photo can usually go lower than a simple illustration.
Does it change the image dimensions?+
No. Only the compression quality is adjusted. The width and height stay exactly the same. Use the resize tool if you need to change dimensions.
What formats does it output?+
JPG and WebP output. Both support lossy compression which is what makes the binary search approach work.
Can I go below 50KB?+
Sometimes, depending on the image. A small or simple image can often go below 50KB. A large high-detail photo may hit a floor before that.