20KB is the ceiling on most exam signature fields. Get under it without dropping below the minimum.
Aim just under, not exactly at
When a portal says “up to 20KB”, some validators read that as less than 20KB and bounce a file that reports as exactly 20.0KB. Landing around 15–18KB avoids the argument entirely, and there is no quality benefit to sitting on the line.
A 20KB signature still has to be readable
Signatures compress well because they are mostly flat white with thin dark strokes — far easier than a colour portrait. You can hold a clean 6cm × 2cm strip at 20KB with no visible loss, provided you started from a decent scan. What ruins it is photographing in poor light, where the paper turns grey and the encoder wastes its budget describing noise instead of ink.
Frequently asked questions
How do I resize my signature to 20KB?
Upload the scanned signature above and choose your exam. The tool crops to the required dimensions and brings the file in under 20KB.
Should the signature be exactly 20KB?
No. Aim a little under. Some validators treat a stated maximum as strictly less than, so a file reporting exactly 20.0KB can be rejected where an 18KB one passes.
Which exams ask for a 20KB signature?
SSC, India Post GDS and many state PSC portals cap signatures at 20KB, usually with a 10KB floor. Confirm against your own notification, since the figures change between cycles.