How to Compress a Photo to 20KB for Online Job and Admission Forms
You fill in a long online application — a government job, a university admission, a scholarship — and at the very end the upload box says: "Photo size must not exceed 20 KB." Your phone photo is 3 or 4 MB. That is about 200 times too big.
The good news: getting a photo under 20 KB is easy once you know what actually controls the file size. This guide shows the fastest way to do it on a phone or computer, without making your face blurry.
Why your photo is so big
File size depends on two things:
- Pixels — a modern phone photo is around 4000 × 3000 pixels, that is 12 million pixels. A passport-style photo on a form is usually shown at just a few hundred pixels wide.
- JPG quality — JPG files can be saved at high or low quality. Lower quality removes fine detail the eye barely notices and makes the file much smaller.
To reach 20 KB you almost always need to reduce both. Reducing only the quality makes the photo blocky; reducing only the pixels is often not enough.
Step 1: Crop away everything you don't need
Forms want your face and shoulders, not the room behind you. Crop the photo so your head fills most of the picture. Every pixel you remove is a pixel the compressor doesn't have to squeeze, so the face stays sharper at the same file size.
You can crop with the editor built into your phone's gallery app. Keep the crop roughly the shape the form shows (often slightly taller than wide).
Step 2: Fix the background before compressing
Many forms ask for a plain white or light background. If yours has a busy wall, curtains or other people behind you, replace it first with a white background photo maker. A plain background also compresses much better than a patterned one, so this step helps the file size too.
Order matters: background first, compression last. If you compress first and then edit, the file gets bigger again.
Step 3: Resize to the exact pixels (only if the form asks)
Some forms give exact dimensions, for example "200 × 230 pixels". In that case, use an image resizer to set those numbers before compressing. If the form only mentions a KB limit, you can skip this step — the compressor in the next step will scale the photo down for you if it needs to.
Step 4: Compress to under 20 KB automatically
Guessing the right quality setting by hand takes many tries. Instead, use a tool that targets the size for you:
- Open Compress Image to 20KB.
- Select your cropped photo. You can select several photos at once.
- The tool tries different quality levels and, only if needed, slightly reduces the dimensions until the file is just under 20 KB.
- Download the result. It is a JPG, which every form accepts.
The photo is processed inside your browser, so it is never uploaded to a server — useful when the picture is for official documents.
Need a different limit? There are versions for 50 KB and 100 KB, and a custom size option for limits like 10 KB or 30 KB (signature uploads often use these).
Step 5: Check the size before you upload
- Windows: right-click the file → Properties → look at "Size".
- Android: open the photo in your file manager and tap the info (ⓘ) button.
- iPhone: in the Files app, long-press the file → Get Info.
Upload systems are strict: if the limit is 20 KB, a 20.4 KB file is usually rejected. Aim to be safely under the limit.
Common mistakes that cause rejection
| Mistake | What to do instead |
|---|---|
| Saving as PNG | PNG photos are many times larger than JPG. Always upload JPG/JPEG unless the form says otherwise. |
| Uploading a screenshot of the photo | Screenshots add extra pixels and status bars. Use the original photo file. |
| Compressing a photo with a busy background | Plain backgrounds compress far better. Fix the background first. |
| Wrong file type (HEIC from iPhone) | Some forms reject HEIC. Convert it with HEIC to JPG first. |
| Face too small in the frame | Crop tighter so your face fills most of the photo. |
Frequently asked questions
Will my photo become blurry at 20 KB?
Not if you crop first. A head-and-shoulders photo of a few hundred pixels stays clear at 20 KB. Blurriness usually comes from trying to keep a full-size 12-megapixel photo under 20 KB.
Can I do this on my phone?
Yes. Everything in this guide works in your phone's browser — no app needed.
What if the form also gives a minimum size?
Some forms say something like "between 10 KB and 20 KB". The 20 KB tool keeps the highest quality that fits, so the result is usually close to the upper limit. If it ever comes out too small, use the custom size tool and enter a value near the top of the allowed range.
Tip: always read the photo instructions on your specific form (size, dimensions, background colour). Requirements differ between organisations and can change from year to year.