Resize a signature to 50 mm × 20 mm
Fifty by twenty millimetres is the signature box on railway recruitment forms. Add your signature, fit the crop box around it, and download a JPG of that size within the file-size range you set.
- Runs in your browser
- Nothing is uploaded
- No sign-up
- No watermark
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Result
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How to use the 50 × 20 mm signature resizer
Add your signature, drag the crop box around it and type the file-size range from your notice. The download is a JPG of 50 × 20 mm, 591 × 236 pixels at 300 DPI. The range starts at 30 to 40 KB, which fits both of the ranges railway notices have used.
- Add your signatureWritten in your normal running hand, in black ink on white paper.
- Fit the box and set the rangeDrag the box around the signature, then type the file sizes from your notice.
- Download the JPG50 × 20 mm at 300 DPI, with the file inside your range.
About this tool
Railway Recruitment Board notices describe the signature as written in running hand, in black ink, inside a box of 50 mm by 20 mm, and uploaded as a JPG at 100 DPI or more. The file-size range is the part that keeps changing. Some notices allow 10 to 40 KB and others 30 to 70 KB, so a file that passed last year can be refused this year.
This page starts with a range of 30 to 40 KB, which sits inside both of those, and you should replace it with the figures in your own notice. The signature is cropped with a box of the 5:2 shape, resized to 591 × 236 pixels, which is 50 by 20 mm at 300 DPI, and saved as a JPG. A signature on white paper is a small file even at that size, so reaching 30 KB usually takes the highest quality setting and some filler data in the file. The result note says exactly what was done.
What you get
- Exactly 50 × 20 mm, at 300 DPI or another resolution
- File-size range you can set to match your notice
- Starts at 30 to 40 KB, which fits both ranges railway notices have used
- Crop box fixed to the 5:2 shape
- Says how the file size was reached, including any filler
When to use the 50 × 20 mm signature resizer
Railway Recruitment Board applications
Notices for railway exams such as NTPC and Group D have described the signature as fitting a box of 50 mm by 20 mm.
A modification window after rejection
When a board reopens uploads for rejected signatures, the replacement has to meet the same box and the notice's file-size range.
Forms that give sizes in millimetres
Other applications that state a signature box in millimetres can be matched by typing their figures in place of 50 and 20.
A minimum that will not be met
A range starting at 30 KB is hard to reach with a small signature image; this page reaches it and says how.
50 × 20 mm in pixels
| Resolution | 50 × 20 mm in pixels | Notes |
|---|---|---|
| 100 DPI | 197 × 79 | The minimum resolution railway notices state |
| 150 DPI | 295 × 118 | A middle setting |
| 200 DPI | 394 × 157 | A common scanner setting |
| 300 DPI | 591 × 236 | The default here: more pixels, so less filler is needed to reach a minimum |
How it works
Two limits pull in opposite directions on this form. The box is small, 591 × 236 pixels even at 300 DPI, and a signature that size is a file of perhaps 10 to 20 KB. The range, on the other hand, can start at 30 KB. Raising the JPG quality to its maximum closes part of the gap. The remainder is filled with data that carries no picture: a comment segment inside the file, which the format provides and decoders skip.
The page starts at 300 DPI to keep that filler small. At 200 DPI the same box is 394 × 157 pixels, fewer than half as many, so the full-quality JPG is smaller and more of the file has to be filler. The notices set only a minimum resolution, so 300 is within the rules, and a higher value still makes more of the file picture. The upper limit is counted at 1,000 bytes to the kilobyte and the lower at 1,024, the stricter reading of each.
Common problems and how to fix them
- The upload is rejected for file size
- Read the range in your notice again; it differs between railway notices. Type both of its numbers into the file-size boxes, then download and upload the new file.
- The result says filler was added
- The image alone could not reach your minimum. That is expected at this size. A higher resolution, such as 600 DPI, makes more of the file picture and less of it filler.
- The signature was rejected as block letters
- Railway boards refuse signatures written in capitals. Sign in your ordinary joined handwriting and upload again in the modification window.
- The signature does not match the one on the day
- Boards compare the uploaded signature with the one you write at the exam and at document verification. Upload your normal signature, not a neater version made for the form.
Frequently asked questions
How many pixels is 50 mm × 20 mm?
394 × 157 pixels at 200 DPI, 197 × 79 at 100 DPI and 591 × 236 at 300 DPI. The formula is millimetres ÷ 25.4 × DPI.
What file size should an RRB signature be?
It depends on the notice. Railway notices have used 10 to 40 KB and 30 to 70 KB. A file between 30 and 40 KB is inside both, which is why this page starts there. Read the notice for your exam and type its limits into the two boxes.
Why does my signature need filler to reach 30 KB?
Because there is very little in the picture. A few pen strokes on white paper, at 591 × 236 pixels, make a JPG of under 30 KB even at the highest quality. The rest is made up with filler data stored in a comment inside the file, which image viewers ignore.
Can I sign in capital letters?
Railway notices ask for a signature in running hand and have rejected signatures written in block capitals. Sign the way you will sign at the exam centre, because the two are compared.
What is 50 mm × 20 mm in centimetres and inches?
5 × 2 cm, or about 1.97 × 0.79 inches.
Does the railway form check pixels or millimetres?
The notices give the box in millimetres with a minimum of 100 DPI, so no single pixel size is fixed. Any resolution of 100 DPI or more gives a valid pixel size for the box.
Can I use this page for the RRB photo too?
The photo on railway forms is 35 × 45 mm, which you can type into the size fields here. For positioning a face, the Passport Photo Cropper is easier, and the Image File Size Reducer will bring the result into the notice's range.