Compress image to 20 KB
Many online application forms ask for a scanned signature or a small photo of no more than 20 KB. Choose your image below: the target is already set to 20 KB. PocketSizePDF finds the highest quality that fits, and reduces the image’s dimensions only if it has to.
This page uses PocketSizePDF’s Image Compressor, where you can also pick exam presets or set any size.
Processed on your device. Your files stay in this browser tab. Nothing is uploaded.
Drop a JPG, PNG or WebP file here
One JPG, PNG or WebP file, up to 15 MB
How it works
- 1
Choose a JPG, PNG or WebP image. It is opened in your browser, not uploaded.
- 2
Keep the target at 20 KB, or change it. Select Compress image.
- 3
Check the preview and the exact file size, then download your image of 20 KB or less.
When you need an image of 20 KB
20 KB is a common upper limit for signature scans and small photos on recruitment, exam and admission forms. At this size an image is shown small on screen, so a few hundred to about a thousand pixels across is usually plenty: in our tests, a 12-megapixel phone photo came out about 1,000 pixels wide at 20 KB.
Tips for a better result
- For a signature, sign in dark ink on plain white paper and crop close to the signature before compressing. Less empty background leaves more of the 20 KB for the signature itself.
- For a photo, crop to your head and shoulders first. Keeping only what the form needs makes the result sharper at the same size.
- If the form also gives exact pixel dimensions, type the width into “Width in pixels”; the height follows automatically.
Size limits differ between forms and change over time, so always check the official instructions for the form you are filling in.
Questions about compressing to 20 KB
Will my image be exactly 20 KB?
It will be no more than 20 KB (20,000 bytes), but not always exactly 20 KB. PocketSizePDF picks the highest quality that fits under the limit, so larger images usually come out just under it — in our tests, between about 95% and 100% of the target. An image that is already smaller than 20 KB stays smaller: files are never padded to reach a number.
Why does the result show a little less than 20 KB?
Two reasons. The result is the largest file that fits under 20 KB, so it is normally a little below it. Also, sizes on screen are shown in units of 1,024 bytes, while the 20 KB limit is counted as 20,000 bytes, so the file passes forms that use either definition of a kilobyte.
Is 20 KB enough for a clear signature?
Yes, for most signatures. A signature is mostly plain background, which compresses very well, so a closely cropped scan usually stays sharp at 20 KB. If yours looks blurry, crop tighter or scan it again in darker ink, then compress again.
What if my image can’t be made 20 KB or smaller?
PocketSizePDF first lowers the quality, then reduces the dimensions step by step while keeping the image clear. If the image still can’t fit without becoming unreadable, you’ll see a message instead of a poor result. Cropping the image first usually solves it.
Is my image uploaded to a server?
No. The image is compressed inside your browser and never leaves your device. You can check the Privacy Policy for details.