Signature fields on SSC, bank and Tamil Nadu recruitment forms rarely give a single limit. The notice prints 10 KB to 20 KB, and a file can miss on either side. The upper figure trips people first, because a phone snap of a signed sheet runs to megabytes. The lower one catches the careful applicant: a neat signature, cropped tight and scaled to a small strip, can weigh as little as 4KB and be refused from below.
This page works inside both numbers from the moment you add a file. A heavy picture loses JPG quality, and pixels as well if quality alone cannot bring it under 20KB. A light picture goes the opposite way: quality climbs to the top setting, and if that still falls short of 10KB, the picture is enlarged in small proportional steps, never past three times its size. The result card shows the final byte count and pixel size, so you can see which direction it took before you download.
How to use it
- Sign with a dark pen on plain white paper, large enough for the ink to fill most of a strip roughly three times wider than it is tall, then scan it or photograph it flat in daylight.
- Crop around the ink, leaving a thin white margin. If your notice fixes pixels or centimetres, make that size first with the signature resizer.
- Add the file here. It runs at once: Maximum file size already reads 20 and the minimum box below it reads 10.
- Check the card: the bytes should read between 10,240 and 20,480, and the pixel size shows whether the picture had to grow. Then download the JPG.
Why a clean signature weighs too little
A JPG is built from small tiles of 8 × 8 pixels, and a tile of flat white costs the encoder next to nothing. The bytes are spent where the pen crossed the paper, mostly along the edges of each stroke. Since ink covers only a small part of a signature picture, the file’s weight follows the length of the lines rather than the size of the sheet. A face photo is the opposite case: almost every tile holds detail, which is why the same 20KB feels tight for a portrait and roomy for a signature.
Quality also has a ceiling. Once the top setting is reached, more pixels are the only honest way to add data. In a test with a signature drawn in black on pure white, a 140 × 60 strip came to roughly 4KB even at maximum quality, and this page had to enlarge it to about 390 × 165 to pass 10KB. The same signature at 472 × 157, which is 6.0 × 2.0 cm at 200 DPI, reached about 14KB without any enlarging. A grey phone photo fails in reverse: paper grain swallows the budget, quality has to fall, and the strokes go soft. Filling the frame with ink and keeping the paper white helps in both cases.
Notices that print the 10 KB to 20 KB band
Staff Selection Commission (CGL, CHSL, MTS, Constable (GD), Stenographer and JE): 10 KB to 20 KB, about 6.0 cm (width) x 2.0 cm (height), JPEG/JPG. These notices say a blurred or miniature signature is rejected summarily, one more reason to sign large.
IBPS (PO/MT, Customer Service Associates, Specialist Officers and RRBs), SBI (PO and Junior Associates), RBI Services Board, NABARD and MIDC: 10 KB to 20 KB, 140 x 60 pixels (preferred), JPG/JPEG, black ink on white paper, not in capital letters. TNPSC: a 6.0 x 2.0 cm box (230 pixels x 75 pixels) scanned at 200 DPI, 10 KB to 20 KB, JPG. TANGEDCO (TNEB exam cell): 4.0 cm x 2.0 cm (preferred) at 200 DPI, 10 KB to 20 KB.
Not every signature field uses this band. The PAN application on the Protean portal wants a signature of at most 10 KB at 2X4.5 cms and 200 DPI, so a file from this page would be too heavy there; the PAN photo and signature page deals with both of its limits.
Frequently asked questions
- Is the 10KB lower limit really checked?
- Some guides call it a soft guideline. The notices print it in the same line as the maximum, as part of the required file size, and you cannot tell in advance whether a portal tests it at upload or later at scrutiny. A file inside the band takes the question off the table, so this page treats 10KB as a firm floor.
- Why did my 140 × 60 signature come back larger?
- At 140 × 60 a clean signature often stays under 10KB even at the highest quality, so the tool enlarged it, keeping the 7:3 shape, until it crossed the floor. The bank notices mark 140 x 60 pixels as preferred, while the 10 KB to 20 KB size carries no such word. If the card says the minimum could not be reached, rescan the signature larger and try again.
- I am applying for India Post GDS. Is 10 to 20KB right?
- Not for the July 2026 schedule. Its notification asks for a signature of 20 KB to 100 KB, recommended 300 × 120 pixels (5:2 ratio), so a 10 to 20KB file would sit under its floor. Before adding the file, set Maximum file size to 100 first and then Minimum file size to 20. Older GDS portal pages still mention a 20kb cap, so go by the notification for your own schedule.
- Does the signature need 300 DPI?
- None of the notices above asks for 300 DPI with this band. TNPSC and TANGEDCO name 200 DPI; the SSC and bank notices give no DPI at all. The weight depends on the pixel count, not on the DPI label, and this page saves a plain JPG with no DPI stored. If a form insists on a stored value, the DPI converter writes one without touching the pixels and adds at most 18 bytes.
- My signature file is already 14KB. Do I need this page?
- Probably not. When a file already falls inside the band, the page says so and offers the original back unchanged, because saving it again can only cost quality. Choose “Convert to JPG anyway” only if the original is a PNG or another format your form will not take.
- Can I get a PDF, or use an app instead?
- The output is always JPG, the format each notice on this page asks for, and nothing needs installing. PDF files are not read here; if your signature sits inside one, take a screenshot of it and add that.