Compress image to 20 KB
Reduce any photo or signature to under 20 KB in seconds. Free, no sign-up, and your image never leaves your device.
- Free, no sign-up
- Files never uploaded
- No watermark
- No limits
Your photo is processed in your browser and is never uploaded.
How to compress an image to 20 KB
- Tap Choose a photo and pick an image from your phone or computer.
- Check the target size. Change it if your form needs something different.
- Tap Download JPG and upload the file to your form.
When do you need a 20 KB image?
Many online application forms for government jobs, entrance exams, scholarships and university admissions limit the photo or signature to 20 KB. A photo from a phone camera is usually 2 to 5 MB, which is 100 to 250 times too big, so the form rejects it.
This tool reduces the photo to under 20 KB and keeps it as clear as that size allows, so your form accepts it the first time.
How the 20 KB compressor keeps your photo clear
DocSlim first looks for the highest JPEG quality that fits under 20 KB. If the photo is still too large, it reduces the pixel dimensions step by step instead of lowering the quality until the photo looks blocky. A 20 KB face photo usually looks sharp at around 400 to 600 pixels wide, which is more than enough for any form.
Tips for a better 20 KB photo
- Crop the photo to your face and shoulders before compressing, so no file size is wasted on the background.
- Use a plain, light background. Plain areas compress much smaller than busy ones.
- For a signature, sign with a dark pen on white paper and photograph it in good light.
- If your form gives exact dimensions, enter them in the width and height boxes above.
Frequently asked questions
How do I reduce a photo to 20 KB on my phone?
Open this page in Chrome or Safari, tap Choose a photo, pick the image from your gallery and tap Download. It works on Android and iPhone without installing anything.
Can I compress an image to 20 KB without losing quality?
Some quality is always lost when a multi-megabyte photo becomes 20 KB, but DocSlim keeps the highest quality that fits and lowers the resolution instead, so faces and text stay clear.
Can I set an exact pixel size, such as 200 × 230?
Yes. Enter the width and height above. The image is cropped from the centre to that exact size and then compressed under 20 KB.
Is my photo uploaded to a server?
No. The compression runs inside your browser on your own device. Your photo is never uploaded, stored or seen by anyone.
Is this tool free?
Yes. It's completely free, with no sign-up, no watermark and no limit on how many images you compress.
Why is the result a little under the limit instead of exactly the limit?
Forms reject files that are even one byte over. DocSlim counts 1 KB as 1,000 bytes and aims just below your limit, so the file passes whether the website counts 1 KB as 1,000 or 1,024 bytes.