Get a photo or signature under 20 KB as a JPG.
Quick answer
Set the target to 20 KB. The tool keeps your photo as it is if it already fits. Otherwise it tries smaller sizes, from 85% down to 10% of the original width and height, and at the first size that fits it raises the JPG quality again so the file lands just under 20 KB.
| Share of original size | Pixels | Bits per pixel at the limit |
|---|---|---|
| 100% | 3000 × 4000 | 0.01 |
| 85% | 2550 × 3400 | 0.02 |
| 70% | 2100 × 2800 | 0.03 |
| 55% | 1650 × 2200 | 0.05 |
| 45% | 1350 × 1800 | 0.07 |
| 35% | 1050 × 1400 | 0.11 |
| 28% | 840 × 1120 | 0.17 |
| 20% | 600 × 800 | 0.34 |
| 15% | 450 × 600 | 0.61 |
| 10% | 300 × 400 | 1.37 |
These figures are computed with the same formulas as the Compress Image to 20KB above. Change the inputs in the tool to see your own result.
Compress Image to 20KB reduces a photo or signature to under 20 kilobytes and saves it as a JPG, the size and format many exam, recruitment and registration forms ask for. The tool looks for the sharpest version that fits: it lowers JPG quality first, and shrinks the picture itself only when quality alone is not enough. For a passport-style photo that means a small but clear image. It works in your browser, so your photo is never uploaded.
Made for everyone. Typical uses:
A 3 MB phone photo of 3000 by 4000 pixels is reduced to a version of about 200 by 270 pixels near 18 to 20 KB, which is typical for a passport-style upload. A signature scanned at 400 by 150 pixels in black ink on white often passes at around 8 to 15 KB.
Twenty kilobytes leaves very little room, so the picture has to be small. It is fine for a form thumbnail but not for printing. The output is always a JPG and transparent areas become white. If the form needs exact pixel dimensions, resize first with the Image Resizer, then compress.
Accuracy: Images are processed with the browser's own image engine and tested with real photos and graphics. Check the result before you use it.
Expert Tip
Crop tightly before you compress. Cropping the photo to just the face and shoulders, or the signature to its ink, removes pixels that would otherwise use up your 20 KB budget, so the part that matters stays sharper.
Twenty kilobytes is about the size of a short email with no attachments. Some application and registration systems ask for photos and signatures at this size so that thousands of uploads stay cheap to store and quick to open. It is a strict limit, and the way to meet it is not to squeeze the file harder but to make the picture smaller and simpler.
A JPG stores colour and brightness for every pixel, so the file size depends mainly on how many pixels there are. A phone photo of 3000 by 4000 pixels holds twelve million of them. A passport-style image of 200 by 270 pixels holds about fifty thousand, which is why it can fit in 20 KB while looking perfectly clear on a form.
The Compress Image to 20KB page looks for the best version that fits. It begins with the original size at high quality. If that is too large, it tries smaller sizes at a moderate quality, and when it finds a size that fits, it raises the quality again until the file is just under 20 KB. The picture is therefore as big and as sharp as the limit allows, rather than needlessly small.
The output is always a JPG with a white background in place of any transparency, because that is what the forms accept. The result panel shows the final size, the new dimensions and whether the limit was reached.
The two common uploads behave differently.
Some portals specify both a file size and exact dimensions, such as a certain number of pixels wide and high. Do these in two steps. First set the dimensions with the Image Resizer or trim the framing with the Image Cropper. Then compress to the size limit. Because the pixel count is already small, the quality stays high.
If the file comes out too small and the portal also states a minimum, raise the target by a few kilobytes and try again, or use the standard Image Compressor with a quality you choose.
Open the result and look at the face, the eyes and the edges of the signature. Make sure nothing is cut off, and that the file name has no characters the portal rejects. Everything happens in your browser, so your photo is never uploaded to us; you can also compress a few versions and keep the best.
If the result looks wrong, it is nearly always one of a few causes: a very large original that had to shrink a long way, a busy background, or a picture that is already dark and noisy. Retaking the photo in even light against a plain wall solves most of them.
A practical process for shrinking website images: right dimensions, right format, sensible quality, lazy loading and a checklist to verify the result.
How to get a photo or signature under a strict KB limit for an exam or job form: crop, choose dimensions, set JPG quality, and avoid the common rejections.
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