How to resize a signature to 10–20 KB for an exam form

Most exam application forms in India ask for a scanned signature of 10 KB to 20 KB, often at an exact size such as 140 × 60 pixels. The size is the easy part. Signatures are usually rejected for other reasons: grey or shadowed paper, faint lines, capital letters, or a signature cut off at the edge.

This guide covers the whole process: signing, photographing, cropping and compressing. Each step heads off one of those problems. If you also need your photo, thumb impression or declaration, see how to compress a photo to 20 KB for an exam form.

1. Check what your form asks for

Find the signature section of your exam’s official notification and note the file size range, the pixel or centimetre size, the format and any ink rules.

2. Sign it the way the form expects

• Use plain white, unlined paper. Ruled or coloured paper shows through after compression.
• Use a black ball-point or gel pen with a good, even line. A very fine pen gives thin lines that can break up at 10–20 KB.
• Sign the way you normally do, in running handwriting. Bank and railway exams reject signatures in capital letters, and your upload must match how you sign at the exam centre.
• Sign a little larger than usual, in a space about twice as wide as it is tall (bank forms use 140 × 60 pixels). A long, thin signature leaves empty space at the top and bottom when it is fitted to that shape.
• Sign two or three times on the same sheet and pick the best one later.

3. Photograph or scan it

• Put the paper on a flat surface in daylight, near a window. Avoid a single overhead bulb.
• Hold the phone flat, directly above the paper, so the signature isn’t slanted or stretched. Make sure your hand and phone don’t cast a shadow on the page.
• Tap the signature on the screen to focus, and keep the flash off. It causes a bright spot and glare on ink.
• A scanner works too, at 200–300 DPI in colour or greyscale.

Look at the photo before moving on. The paper should look white, not grey or yellow, and the lines should be solid and dark. Compress Image keeps the photo exactly as it is: it does not whiten paper or remove shadows, so retaking a poor photo is quicker than fixing it.

4. Crop and compress it

First, crop the photo in your phone’s gallery to the one signature you want, leaving a small margin of white paper all round. Cropping close matters: the signature should fill most of the image, not sit small in the middle of a page.

1. Open Compress Image.
2. Under Target size, tap 20 KB (or type the form’s maximum).
3. Tap More options. Set Minimum KB, and if the form gives a pixel size enter it as Width (px) and Height (px). Keep the format on JPG.
4. Choose the cropped signature photo and tap Compress.
5. Compare it with the original. Every stroke should still be clear, then download it.

With a width and height entered, the image is trimmed evenly from the edges to that shape — never stretched. If part of your signature gets cut off, crop again in your gallery with a little more margin on the sides that were trimmed.

Settings for common exams

Each minimum is two above the form’s figure, so the file passes whether the portal counts 1 KB as 1,000 or 1,024 bytes. “Blank” means leave width and height empty: the form gives no exact pixel size (SSC gives centimetres; RRB gives only a minimum that a phone photo already exceeds), so your cropped photo keeps its own shape. For UPSC, any size inside the allowed range works; 800 × 400 is simply a convenient one.

If the portal rejects your signature

• The tool says it can’t reach the minimum. Signatures are mostly white paper, so they compress to very small files. This happens most with the larger RRB and UPSC minimums. Use the uncropped original or a larger pixel size, if the form allows one, so there is more detail to keep.
• “File size is too small.” Set Minimum KB a little above the form’s figure, as in the table above, and compress again.
• Lines look broken or faint. Sign again with a thicker black pen and photograph in better light. Cropping closer also helps, because more of the image is ink.
• The background looks grey or patchy. That is shadow or dim light in the original photo. Retake it in daylight, with the phone held so it casts no shadow.
• Part of the signature is cut off. Crop again with more margin, or sign in a shape closer to the form’s width-to-height ratio.
• “Invalid file type.” Check that the format under More options is JPG. A PNG or iPhone HEIC photo comes out as JPG once it has been through the tool.

Why it matters where you resize it

A clean image of your signature is exactly what someone would need to forge it on a document. Many online resizers upload the image to a server to process it, and you can’t see what happens to it there.

Velprio’s Compress Image works in your browser, on your own phone or computer, so the signature is never sent anywhere. You don’t have to take our word for it: the Security page explains how to check it in your own browser.