Compress signature to 20KB for SSC and bank exams.

Why exam portals reject signatures

Signature rules are stricter than photo rules because a signature is mostly thin ink lines on white — it degrades faster under compression. SSC and IBPS commonly require 10KB–20KB in JPG format at roughly 140 × 60 pixels, black ink on plain white paper. Portals reject signatures that are too large, too blurry to read, or photographed at an angle. If your photo passed but the form still errors, the signature is the usual culprit — see the exam photo and signature size guide for the full limits table.

Scan a clean signature first

Compression cannot rescue a bad scan. Ten minutes of care here saves repeated rejections.

What ink and paper to use

Sign with a black gel or ballpoint pen on plain, unlined white paper. Blue ink compresses worse because portals convert to grayscale and blue maps to a lighter grey, thinning your strokes. Avoid ruled notebooks — the lines add noise that eats bytes.

How to photograph it

Use daylight near a window, not yellow indoor light. Hold the phone parallel to the paper to avoid perspective skew, fill the frame with the signature, and tap to focus on the ink. Take three or four shots and pick the sharpest — zoom in and check that stroke edges look crisp, not fuzzy.

Crop tightly to about 140 × 60 pixels

Every millimetre of white margin around your signature is wasted bytes. Crop so the ink nearly touches the edges of the frame, then resize to roughly 140 × 60 pixels — the dimensions SSC and IBPS publish. A tight crop concentrates the byte budget on ink detail instead of empty paper, which is the single biggest quality win for signatures.

Compress to the exact target in SizeMint

1. Note your form's range

Check the notification: most ask for 10–20KB. Target the middle — around 15KB — so you clear both the minimum and the maximum with margin.

2. Upload and set the target

Open the SizeMint compressor, drop in your cropped signature, and enter the target size. The compressor searches encodings automatically for the best quality that fits, instead of making you guess a quality number.

3. Inspect the strokes

Zoom in on the result. Strokes should stay solid black; if they turn grey and broken, your source scan was too soft — rescan in better light rather than pushing the target lower.

4. Verify before uploading

Confirm the downloaded file's size in your file manager and check it opens as a valid JPG. Keep the original scan for other forms with different limits.

Troubleshooting signature problems

Blurry after compression: the source was the problem, not the target. Rescan sharper — compression only preserves detail, it never creates it.

Portal says invalid dimensions: resize to 140 × 60 before compressing. Some portals check pixel dimensions separately from file size.

File below the 10KB minimum: raise the target toward 15–18KB. An undersized file fails just like an oversized one.

Signature compression FAQs

What size should my SSC signature be?

Commonly 10KB–20KB, JPG, around 140 × 60 pixels. Always confirm against your cycle's official notification.

Can I use blue ink?

Black is safer. Portals often grayscale the image, and blue ink renders lighter, which can make strokes look faint or broken.

Why does my signature look blurry after compressing to 20KB?

Almost always a soft source photo. Retake it in daylight, focused on the ink, then compress again.

My form asks for a 10KB signature, not 20KB. What changes?

Only the target number: enter 10KB and inspect the strokes carefully. At 10KB a tight crop matters even more.

Related guides

Doing the photo too? Read the exam photo and signature size guide for every exam's limits. For the general exact-size technique, see how to compress an image to 20KB.