Resize an image to 20 KB

A 20 KB file is very small, roughly the size of a short text email with a thumbnail. Forms that ask for it usually want a small passport-style photo or a signature image.

Quick answer: Choose your image, keep the target at 20 KB, and download a JPG that is at or just under 20 KB. It runs in your browser and nothing is uploaded.

1. Add images
2. Choose settings
3. Download

Choose imagesor drop them here, or paste with Ctrl+V. Up to 40 at once. They stay on your device.

Output format

JPGWebPPNG

How to shrink

Exact size (KB)Quality

Target size (KB)

Resize (optional)

Max width (px)

Max height (px)

Leave blank to keep the original size. Images are scaled to fit and are never enlarged.

Your settingsChanging any option re-compresses your images automatically.

Files processed0

Total saved0 B

Average reduction0%

Original to result-

How to resize an image to 20 KB

1. Choose your image. Click the box or drop a JPG, PNG or WebP file onto it. It opens inside your browser and is not uploaded.
2. Check the target. It is set to 20 KB. Aim a little below the limit on your form, because some systems count 1 KB as 1,000 bytes.
3. Compress and compare. The tool finds the highest quality that fits. Drag the comparison slider to see what changed.
4. Download and check. Open the saved file at full size before you upload it, especially if it contains text or a face.

What fits in 20 KB

A small portrait or signature image. A full-size phone photo cannot fit at 20 KB without being shrunk a lot.

As a rough guide, 20 KB holds about 136,533 pixels at moderate JPEG quality. Real files vary with how detailed the picture is, so treat these as estimates:

Why 20 KB is hard for photos

A JPEG file stores detail, so its size depends on how many pixels it has and how busy the picture is. At 20 KB you have about 163,000 bits to spend. At a moderate quality of roughly 1.2 bits per pixel that is around 136,000 pixels, or a square of about 370 by 370 pixels.

A 12-megapixel phone photo has about 12 million pixels, so it has to shrink by roughly 90 times in pixel count before it can fit. That is why this tool lowers the quality first and then the pixel dimensions: the number you see in the result panel tells you what it had to give up.

Signatures and stamps compress best

A signature on plain white paper is mostly empty space, which JPEG stores very cheaply. Sign with a dark pen, photograph or scan it in even light, and crop tightly around the signature before compressing. A well-cropped signature will often land well under 20 KB with no visible loss.

Avoid shadows across the paper. A grey gradient costs more bytes than white and can make the signature look washed out after compression.

Preparing a portrait for 20 KB

For a portrait, crop closely around the head and shoulders before you compress, and use a plain background. Patterned walls, curtains and busy backgrounds use up bytes that the face needs.

Check the form for a minimum width and height as well as the size limit. If the tool had to shrink the image below that minimum, you may need a bigger target or a closer crop instead.

Tips for 20 KB

• Crop the photo to the face or signature first. Less empty background means more of the 20 KB goes to what matters.
• Signatures on a white background compress much better than photos, often well under 20 KB with no visible loss.
• If the tool had to shrink the pixel dimensions, check that the form does not also require minimum dimensions.
• Aim a little below the stated limit, because some systems count 1 KB as 1,000 bytes rather than 1,024.

If something goes wrong

• The result is still above 20 KB: crop closer, or start from a smaller original, then try again.
• The face looks blurry: crop tighter so the face uses more of the frame, rather than lowering the quality further.
• The upload is rejected for dimensions: check the minimum width and height on the form, and raise the target if you must.
• The format is rejected: choose JPG; some portals do not accept WebP.

JPG, WebP or PNG?

JPG is accepted almost everywhere and is the safe choice for forms. WebP is usually smaller at the same visual quality but some upload portals reject it. PNG keeps sharp edges for screenshots and logos, but it is rarely small enough for a strict KB limit, which is why this tool outputs JPG or WebP.

The limit on your form may differ from 20 KB. Use the number the form states, and leave a little margin below it.

Need a different limit? Use the image compressor with any size. For passport or ID photos, set the dimensions first with the photo size tool.

Other sizes

50 KB · 100 KB · 200 KB · 500 KB

Last reviewed 2026-10-21.