What is the RRB Railway signature size?
Recent Railway Recruitment Board notices for NTPC, Group D and ALP ask for a JPG signature between 30KB and 49KB, at least 140 × 60 pixels and 100 DPI, signed inside a box of 35 mm × 20 mm on white paper. This RRB signature resizer crops your signature to that box, sizes it at 200 DPI (276 × 157 px) and keeps the file inside 30–49KB. Plain signatures are naturally tiny, so the tool adds a harmless padding block to reach 30KB. The photo is now taken as a live photo, so the signature is the main file you upload. Check the CEN on the RRB website before applying.
RRB signature specifications
| Rule | Recent CEN notices |
|---|---|
| File size | 30KB – 49KB |
| Format | JPG / JPEG |
| Minimum pixels | 140 × 60 px |
| Resolution | 100 DPI or more |
| How to sign | Black ballpoint inside a 35 × 20 mm box on white, unruled paper |
| Photo | Live capture by webcam or mobile, not a file upload |
Each RRB publishes the same Centralised Employment Notice (CEN). Read it on rrbapply.gov.in or your regional RRB site linked from indianrailways.gov.in.
Why the 30KB minimum causes trouble
A signature is mostly white paper. Saved as a 276 × 157 px JPG it is usually only 5–10KB, far below the RRB minimum. Many candidates then upload a huge, uncropped phone photo just to cross 30KB, and it gets rejected for showing the table, fingers or shadows. The better fix is to keep a clean, cropped signature and add invisible padding data inside the JPG. The picture stays exactly the same, but the file size reaches 30–49KB and the portal accepts it.
How to resize your signature for RRB
- 1Draw the 35 × 20 mm box
Use a ruler on plain white paper and sign inside it with a black ballpoint pen.
- 2Photograph the box
Keep the phone straight above the paper in good light.
- 3Upload with the RRB preset
276 × 157 px and 30–49KB are set; auto-crop removes the extra paper.
- 4Download when ✓ Valid
Upload the JPG in the signature step of the RRB application.
RRB signature mistakes to avoid
- Signing outside the box. Keep the whole signature inside 35 × 20 mm.
- Capital letters. RRB asks for your running signature.
- Ruled notebook paper. Lines show up and the image looks dirty.
- File over 49KB. Large phone photos fail; the tool caps the size for you.
Prepare other Railway documents
Certificates and caste or EWS proofs can be reduced with Compress PDF to 200KB or Resize PDF for Application Form. If a recruitment asks for an uploaded photo, use Photo to 50KB. A shadowed signature sheet can be cleaned first with Clean Signature Background. All processing happens on your device.
Frequently Asked Questions
What is the RRB signature size?
Recent RRB CEN notices ask for a JPG signature between 30KB and 49KB, at least 140 × 60 pixels and 100 DPI.
What is the 35 × 20 mm box?
RRB asks you to draw a box of 35 mm × 20 mm on white paper and sign inside it with a black ballpoint pen. This tool sizes the image to that box at 200 DPI.
Why is a clean signature smaller than 30KB?
Plain white paper with thin strokes compresses very well. The tool adds a harmless padding block inside the JPG so it reaches 30KB.
Does RRB still need a photo upload?
Recent RRB forms capture a live photo through webcam or mobile camera, so only the signature needs to be uploaded as a file.
Can I sign in capital letters?
No. RRB asks for your running signature, not capital letters.
Is my signature uploaded to PhotoKB?
No. It is processed in your browser only.
About this tool
Built and maintained by the PhotoKB Editorial Team. We test every tool with real phone photos, scans and PDFs before each update. Exam and portal values are based on public official notifications. PhotoKB is not linked to any exam body, so always confirm current rules on the official website. Last updated: 8 November 2026.