Compress image to a target file size in KB

Need a photo under a specific size limit? This free tool lets you compress an image to a target file size in KB, right in your browser. Just set the maximum KB you need and it finds the highest JPEG quality that fits under your limit, automatically scaling the image down when the target is very small. It is perfect for upload forms, email attachments and websites that cap image size, and the achieved size is shown next to your target so you know exactly what you got. Everything runs 100% in your browser — your image is never uploaded, so it stays private, and the tool is completely free.

🔒 100% private — files never leave your device

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How to use

  1. Select or drag and drop an image (JPG, PNG, WebP, HEIC or any image your browser can open).
  2. Enter the target file size in KB (the default is 100 KB).
  3. Click Compress and let the tool find the best quality under your limit.
  4. Download the compressed JPG image to your device.

Frequently asked questions

What image formats can I compress?

You can load any image your browser can open, including JPG, PNG, WebP and often HEIC. The result is always saved as a compressed JPG, which gives the most reliable control over file size.

Is my image uploaded to a server?

No. The entire compression runs in your browser on a canvas, so your image never leaves your device and nothing is uploaded. It is completely private.

How does it hit my exact target size in KB?

The tool binary-searches the JPEG quality to find the highest setting whose file size stays at or under your target in KB. If even the lowest quality is still too big, it scales the image down step by step until it fits.

What if my target size is too small to reach?

If your KB target is extremely tight, the tool reduces quality and dimensions as far as it can and always produces the smallest achievable result, showing you the size it actually reached.

Why is the output a JPG and what about transparency?

JPEG gives fine, predictable control over file size, so it is used for the output. Because JPEG does not support transparency, any transparent areas in a PNG or WebP become solid and transparency is lost.

Is there a file-size limit and does it cost anything?

The tool is completely free with no sign-up. Because processing happens in your browser, the practical limit is your device's memory; very large images simply take a little longer to compress.

About this tool

Free online tool to compress an image to a target file size in KB. Set your limit and download a smaller JPG. Runs 100% in your browser — no uploads, fully private.

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