Resize an image to 20 KB

20 KB is the floor of the range portals quote. SSC CGL wants a signature at 140×60 px and 10–20 KB. Several state portals cap a scanned document at 20 KB outright. It is also where the two rules on the form start to fight each other.

At 140×60 px — a signature — 20 KB is generous; a signature is mostly white and compresses to a few kilobytes. At 200×230 px, a colour photograph of a face, 20 KB is tight and the result will visibly soften.

Above that, the file size stops being the thing that fails. Here is a real run on this page: a 1200×1200 photograph of 1,011 KB came back at 19.1 KB, still 1200×1200, by dropping JPEG quality to 10%. It fits. It is also a photograph that a person looking at it may well refuse, and no size check will ever catch that. The limit was met and the submission can still fail.

So the number that matters is the quality, and this tool prints it. Every result line shows the size it reached and the quality it had to drop to — 10% in that run — because that is the figure telling you whether to submit the file or go back and change something. A resizer that returns a 20 KB file and says nothing else has answered the easy half of the question.

And it does not reach the target by cheating on the other rule. It keeps the dimensions you typed rather than quietly shrinking the picture, and on the occasions when even 1% quality will not fit, it says so and shows the closest it reached instead of handing back something that looks finished.

If you need the picture smaller as well, untick the setting that holds the dimensions and it is allowed to reduce them — deliberately, and with you knowing, which is the whole difference.

Nothing leaves the device. Open your network tab: the page loads its own files, and a finished job sends one empty request to this domain so it can be counted. No analytics vendor, no tracker, no third-party request of any kind — here is exactly how.

If the result comes back at a quality you would not want a stranger to judge you on, three things help, in this order. Reduce the pixel size if the form allows any — halving the width and height cuts the pixel count to a quarter, and every pixel you remove is quality you get to keep on the ones that remain. It does far more than any quality setting can. Crop the empty space: a signature photographed on a whole sheet of paper is mostly paper, and the paper is costing you the bytes. Convert to JPG if the file is a PNG — a photographic image stored as PNG can be several times larger for no visible gain.

The general shape of it: 20 KB is nearly always reachable, and the question is what it costs. Read the quality figure on the result line before you upload, not after.