10 KB image size — the PAN signature ceiling and how to reach it without a smudge
Ten kilobytes is the smallest ceiling on a mainstream Indian form, and it belongs to one field: the signature on a Protean PAN application.
JPG, PNG, WebP · up to 50 files at once · nothing is uploaded
10 KB image specification
| Requirement | Value |
|---|---|
| PAN signature (Protean) | JPEG, maximum 10 KB, scanned at 200 dpi, printed area 2 cm x 4.5 cm |
| PAN photograph (Protean) | Colour JPEG, maximum 20 KB, 3.5 cm x 2.5 cm at 200 dpi — twice the signature budget |
| PAN supporting documents | Black-and-white PDF/A or JPEG, maximum 300 KB per page |
| Pixel size that fits | About 350 x 160 px for ink on white paper; roughly 200 x 250 px for a face |
| Ink and paper | Black or dark-blue pen on plain white paper, scanned as colour or greyscale, not as a 1-bit line drawing |
| Floor | None published — 10 KB is a ceiling only, so a 6 KB file is fine |
| Common mistake | Uploading a phone photo of the signature with the desk still in frame |
Source: Guidelines for Online PAN application with DSC — Protean eGov (TIN-NSDL) (live instructions page on tin.tin.proteantech.in, read September 2026). checked on 2026-09-20. The page gives the signature box as 2 x 4.5 cm and the photo as 3.5 x 2.5 cm; the physical Form 49A prints the same boxes, so the numbers agree.
Why the smallest limit belongs to a signature
The Protean PAN instructions give every upload a different budget: the photograph may be up to 20 KB, each supporting page up to 300 KB, and the signature no more than 10 KB. The reason is physics rather than stinginess. The signature box on Form 49A is 2 cm tall and 4.5 cm wide, and at the 200 dpi the same page asks for, that box is only about 160 x 350 pixels. A few strokes of dark ink on white paper inside that rectangle compress to a handful of kilobytes without any visible loss. The limit is small because the content is small.
Trouble starts when people photograph the signature instead of scanning it. A phone frame includes the desk, the edge of the page, a shadow from the hand, and the paper's grain — all of it costs bytes and none of it is the signature. Cropping to the rectangle before compressing removes most of the problem on its own.
What ten kilobytes can and cannot hold
A JPEG stores detail, not area. A flat white background is almost free, while a face with skin texture, hair and a patterned shirt is expensive. That is why a 350 x 160 px signature fits in 7 KB while a face of the same pixel count would be soft and blocky. If a portal ever asks for a photograph at 10 KB, treat it with suspicion: the 20 KB page explains how that number usually turns out to be the floor of a 10-20 KB window rather than a ceiling.
Matching the printed acknowledgement
PAN is unusual in that the uploaded signature is compared against ink later — on the acknowledgement you sign and post, and on the physical card. Sign the way you always do, in running hand, at the size you would sign a cheque. A tiny, cautious signature that fills a quarter of the box scans badly and looks nothing like your everyday one. The PAN card photo page covers the matching photograph rules, and the 10-20 KB signature page covers the banking range that shares the same scanning technique with a slightly larger budget.
How it works
- Sign inside a 2 x 4.5 cm rectangle on white paper with a black or dark-blue pen.
- Scan at 200 dpi, or photograph straight-on in daylight without shadow.
- Crop hard to the rectangle so no desk, hand or page edge remains.
- Leave the maximum at 10 KB; there is no floor, so ignore the minimum field.
- Confirm the badge shows a match and the strokes are still solid at 100% zoom.
- Save as signature.jpg and reuse the same file for any PAN correction later.