Compress Image to 20KB
Get a photo or signature under 20 KB for an online form, sharp and readable.
Drop images here
JPG, PNG, WebP, GIF, BMP, TIFF, HEIC or camera RAW — as many as you like
Files are processed on this device. Nothing is uploaded.
How to use Compress Image to 20KB
- Drop your photo or signature (or several).
- 20 KB is already selected, with Make the picture smaller if needed ticked, so the result stays sharp. If your form also fixes the pixel size, use the Photo & Signature Resizer instead.
- Select Compress images and check each result says it is under 20 KB.
What fits in 20 KB
20 KB is about 20,000 bytes: enough for a passport-style face photo of roughly 300–600 pixels on the long side, or a signature, but not for a full phone photo. A 12-megapixel photo has 12 million pixels; squeezing it into 20 KB by lowering the quality alone gives a blocky, unusable image. The useful way is to reduce the pixel size first, then use a good quality setting.
That is what this page does automatically: it searches for the highest quality that fits; if that would drop below 60% (where JPEG blocks become visible), it shrinks the picture to the largest size at which it still fits at good quality, and shows you the final dimensions.
Upload forms that ask for 20 KB are usually for a photo (often 10–50 KB) or a signature (often 10–20 KB). If the form also demands exact pixels such as 140 × 60 or 200 × 230, use the Photo & Signature Resizer, which sets the pixels and the KB range together.
Measured: the largest size that fits in 20 KB
A 21-megapixel camera photo fitted in 20 KB at 455 px on the long side at quality 85%, 552 px at 75% and 644 px at 60%. A more detailed photo fitted at 274, 321 and 367 px. Simple pictures such as signatures fit far larger.
Frequently asked questions
How do I reduce a photo to 20 KB without losing quality?
Some quality is always lost at 20 KB, but it stays sharp if the picture is made smaller in pixels rather than compressed harder. This page does that automatically; expect a picture about 300–600 px on the long side.
How do I compress a signature to under 20 KB?
Photograph the signature on white paper, crop it closely, then drop it here. Signatures are simple, so they fit 20 KB easily. For an exact size such as 140 × 60 px, use the Photo & Signature Resizer.
Why is my result smaller than I expected in pixels?
Because 20 KB is very little data. A sharp 450 × 600 photo looks better on a form than a blurry 3000 × 4000 one. Untick “Make the picture smaller if needed” to keep the dimensions and accept lower quality.
Can I compress several images to 20 KB at once?
Yes. Add as many as you like and download them separately or as a ZIP.
Are my photos uploaded?
No. Compression happens in your browser; nothing leaves your device.
Limitations
- Very detailed photos may need to be under 300 px on the long side to fit.
- Animated GIFs become still images.
- For fixed pixel dimensions use the Photo & Signature Resizer.
Guides for this tool
- How to Resize a Signature to 10–20 KB (and Why It Fails)Forms ask for a signature of 10–20 KB, but a 140 × 60 px signature is only 3–6 KB even at full quality. We measured it. Here is what actually works, step by step.
- How to Check if an Online Tool Uploads Your FilesA 2-minute test with your browser’s developer tools shows whether a PDF or image tool sends your file to a server. Step by step, for Chrome, Edge, Firefox and Safari.
- How to Compress an Image to 100 KB, 1 MB or Any SizeUpload forms often demand images under 100 KB or 2 MB. How JPEG quality and pixel size affect file size, and the fastest way to hit a limit without ruining the photo.
- JPG vs PNG vs WebP vs AVIF: Which Image Format to UseA practical guide to choosing image formats for photos, screenshots, logos and websites, with the trade-offs in size, quality, transparency and compatibility.
Last reviewed November 9, 2026. How we build and test tools.