How to Compress a Photo to 20 KB, 50 KB or 100 KB for Online Forms

Oct 24, 2026 · 5 min read · Media

Online application forms are strict about file size. A form might ask for a photo "between 20 KB and 50 KB" or "under 100 KB", and a picture straight from a phone camera is usually 2 to 5 MB. That is fifty to two hundred times too big. This guide shows how to get any photo under an exact size in a few clicks, and why the usual tricks often fail.

The quick way: set a target size

1. Open the free image compressor.
2. Type the size you need, for example 20, 50 or 100, into Target size (KB). You can also pick "Under 20 KB", "Under 50 KB" and similar from the preset menu.
3. Add your photo by clicking the upload box or dragging the file onto the page.
4. Check the result line. It shows the new size and a tick when the file is under your target.
5. Click Download and upload that file to the form.

The tool tries many quality levels and keeps the best one that still fits. Only if even the lowest quality is too large does it also make the picture smaller in pixels, and it tells you when it has done that. Everything happens in your browser, so the photo never leaves your phone or computer.

Why a photo is so large in the first place

File size depends on two things: how many pixels the picture has and how much detail the format keeps for each one. A modern phone takes photos of 12 to 50 megapixels, far more than any form needs. A passport-style photo on a form is shown at about 200 to 400 pixels wide, so most of those pixels are wasted.

The format matters too. JPG throws away detail the eye barely notices, which is why it is the right choice for photos. PNG keeps every pixel exactly, which makes photos much bigger. If your file is a PNG or a screenshot, converting it to JPG often cuts the size by 80% or more on its own.

Common sizes forms ask for

• Under 20 KB: common for signatures and thumb impressions.
• 20 to 50 KB: the most common photo range for SSC, banking and many state exams.
• Under 100 KB or 200 KB: typical for university, scholarship and job portals.
• Under 1 MB: usually for document scans rather than photos.

For exam forms with fixed pixel sizes, use the exam presets instead. They crop the photo to the right shape as well as the right size. See our guides to the SSC photo and signature size and the IBPS and SBI photo size.

What if the form says the file is too small?

Some portals reject files below a minimum, such as 20 KB. A small, plain photo can come out at 12 KB even at full quality. When you choose an exam preset with a minimum, the tool adds harmless padding inside the JPG file so it lands just above the minimum. The picture itself does not change, and the file opens normally everywhere.

Mistakes that get photos rejected

• Taking a screenshot of the photo. It adds your phone's border and saves as PNG, which is often larger, not smaller.
• Compressing an already compressed photo again and again. Each round adds blur. Always start from the original photo.
• Wrong format. If the form says JPG or JPEG, do not upload PNG or HEIC. The target-size option always saves JPG unless you choose WebP.
• Wrong shape. A size limit in KB is not the same as a size in pixels or centimetres. Check both in the notice.

Keep the photo looking good

At 20 KB a small photo of about 200 by 230 pixels still looks sharp, but a large photo forced down to 20 KB will look blurry. If the form only asks for a KB limit, first set a sensible Max width such as 600 pixels, then set the target size. Fewer pixels means each one can keep more detail. Good light when you take the photo also helps far more than any setting, because a dark, noisy photo has more "detail" for the file to store.

Frequently asked questions