Image Tools
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Resize Image to KB

Fit a photo or signature into any limit, such as under 50 KB or between 20 and 50 KB, and keep it sharp.

Runs in your browserNo sign-up requiredNo watermark

Drag & drop an image, or click to browseTap to choose an image

Common limits

Quality is kept high; if that's not enough to reach your limit, the image is made smaller in pixels instead, which looks far better than heavy compression. Filling in an exam form? The Exam Form Kit also sets the exact pixel size each exam asks for.

Add an image to fit it to your size limit.

What Is This Tool For?

Some upload forms — exam applications, ID verification, government portals — enforce a strict file size limit like "under 50 KB". Manually dragging a quality slider and re-exporting until you land under the limit is slow and imprecise. This tool automatically searches for the highest quality that still fits your target size, so you get the best possible result in one step instead of five failed attempts.

How to Use This Tool

  1. 1Add your photo or signatureJPG, PNG, WebP or iPhone HEIC. It stays on your device.
  2. 2Set the limitTap a preset such as "Under 50 KB" or "Exam photo 20–50 KB", or type the maximum (and a minimum, if the form asks for one).
  3. 3Check the resultIt updates by itself and shows the exact size in KB and bytes, the pixel size and the quality used. Drag the line to compare with the original.
  4. 4DownloadThe file lands just inside your limit, so strict upload portals accept it.

How It Fits Your Limit

  1. 1Start with a sensible sizeFrom the limit and the photo's size, the tool estimates how many pixels will fit at good quality, so a 12-megapixel photo heading for 50 KB doesn't waste time at full size.
  2. 2Find the best quality that fitsAt that size it searches between 60% and 95% quality for the highest setting that stays under your limit.
  3. 3Adjust the pixel size if neededIf even 60% quality is too big, the image is scaled down a little and the search repeats. If there is room to spare, it scales back up. For a minimum size it can raise the quality, or the size, to reach it.

Good to Know

  • Most forms that say "between 20 KB and 50 KB" reject files that are too small as well as too big. Set both numbers and the tool fits inside the range.
  • The tool keeps quality between 60% and 95%. If that isn't enough to reach a small limit, it reduces the pixel size instead, which looks much better than crushing the quality.
  • Files are aimed a little inside the limit, because some portals count 1 KB as 1,000 bytes and others as 1,024.
  • Use JPG for forms: every portal accepts it. WebP is smaller but some government sites don't allow it.
  • Transparent PNGs, like a signature on a clear background, are filled with white (or a colour you choose) when saved as JPG.
  • For exams with a required pixel size too, the Exam Form Kit sets both the pixels and the KB range from the official notice.

Frequently Asked Questions

Why do some forms require an exact file size limit?

Many government and institutional upload forms cap file size to keep their systems fast and storage costs predictable — they often specify both a maximum (and sometimes minimum) size in KB.

Can this hit an exact KB number, like exactly 50 KB?

It lands just under the number you set (about 2% inside, so every portal accepts it). Image compression can't hit an exact byte count, but for upload limits only the maximum and minimum matter.

Why did the pixel size of my photo change?

Reaching a small limit like 20 KB from a large phone photo only by lowering quality would leave it blocky. Reducing the pixel size keeps faces and text sharp. The tool shows the new size; most forms ask for small pixel sizes anyway.

What if my target size is smaller than what's achievable?

The tool will return the smallest reasonable result it can produce and note that it couldn't fully reach your target — going lower would need reducing the image's pixel dimensions too, which this tool doesn't do automatically. Try the Image Resizer first to shrink dimensions, then compress the smaller result.

Does this change my image's width and height?

No — only the compression quality is adjusted. If you need to hit a target size and the dimensions are also flexible, resizing first gives the compressor more headroom to hit a lower target at better quality.

Is my image uploaded to a server?

No — the entire compression search happens in your browser.