Compress Image to 20 KB
For signatures and photos on forms with the tightest limits
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For signatures and photos on forms with the tightest limits
Twenty kilobytes is the tightest limit you are likely to meet, and it usually appears in the same place: the signature box on an online application form. Upload your scan or photo, and it comes back under 20 KB, measured in real bytes rather than estimated. No account, no watermark, nothing kept on our servers.
A limit this low is rarely about your file. It is about the millions of other files. An examination body handling a few hundred thousand applicants, each uploading a photo and a signature, is looking at a storage and bandwidth bill that scales directly with the cap it sets. Many of these systems were also specified years ago, when a 20 KB ceiling was generous rather than punishing, and nobody has revisited the number since.
The practical effect is the same either way. A modern phone photo arrives at three or four megabytes - roughly two hundred times over the limit - and the form rejects it with an error message that rarely explains what to do next.
Signatures are the most common thing squeezed into this limit, and the most commonly botched. A few things make the difference between a clean upload and a rejected one:
Plenty of forms ask for something between a minimum and a maximum - between 10 KB and 20 KB is a common pairing. The maximum is the easy half, and the tool handles it by aiming just under your target rather than far below it.
The minimum can catch you out. A signature is a few dark strokes on white, which is almost no information at all, and JPEG will happily store it in five or six kilobytes even at maximum quality. If your result comes back well under the minimum, the fix is not more compression - it is more image. Rescan or rephotograph the signature at a larger size, or crop a little less tightly, and run it through again.
More than people expect. Twenty kilobytes comfortably holds a head-and-shoulders portrait at around 400 by 500 pixels at readable quality - larger than most forms display it. A signature needs far less than that.
Where it hurts is full-frame photographs with a lot going on: a landscape, a group shot, a photo of a full page of dense text. Those carry too much detail to survive this limit intact, and the honest answer is that they will come back visibly reduced. If the form is asking for a document rather than a portrait, check whether it really wants 20 KB - 100 KB is far more usual for scans.
Yes, for a head-and-shoulders photo. The tool lowers quality first and reduces pixel dimensions only when it has to, so the photo stays as large as the limit allows rather than being shrunk to a thumbnail unnecessarily.
Because a few dark strokes on a white background is almost no information. JPEG stores it in a handful of kilobytes even at maximum quality. Nothing is wrong with the file, but if your form enforces a minimum size you will need a larger scan.
JPG. It is the only common format with a quality dial fine enough to hit an exact byte target, and it is what these forms accept. Need something else afterwards? The Image Converter handles that.
Yes, and most people do. Shoot straight down in even light and crop before you upload. HEIC files from an iPhone are accepted and come back as JPG.
No. It is held in memory only for as long as the compression takes, then discarded. The EXIF metadata your camera wrote - including GPS coordinates - is not carried into the file you download.
Use the full Compress to Exact Size tool and type any target from 5 KB to 5000 KB, or jump straight to 50 KB or 100 KB.