Quick answer
Sign on plain white paper with the pen colour the notification asks for, and take a clear photo. Crop it tightly with Image Resize & Crop. Then open Compress Image to KB, choose JPEG, set the pixel size if the form gives one, type a KB target inside the allowed range, and download.
Check the notification first
Every exam and portal sets its own rules, and they can change from one year to the next. Copy these four things from the current notification before you start:
- File size range, for example "10 KB to 20 KB".
- Pixel or cm size, if given.
- Format, usually JPG or JPEG.
- How to sign: ink colour, running handwriting or not, and whether to sign once or several times.
To show how much the rules differ, here are examples reported for 2026 application cycles. Treat them as examples only and confirm in your own notification.
| Exam (2026 cycle, as reported) | Signature size | Dimensions | Note |
|---|---|---|---|
| SSC CGL | 10 to 20 KB, JPEG | about 4.0 cm x 2.0 cm | Photo is captured live during the application |
| IBPS RRB | 10 to 20 KB | 140 x 60 pixels | Running handwriting, not capital letters |
| UPSC | 20 to 100 KB, JPG | 350 to 500 pixels | Sign three times on one sheet and scan them as one image |
Step by step
- Sign on clean white paper. Use a good pen and sign a little larger than usual, so the signature stays clear after shrinking.
- Take the photo. Use daylight, hold the phone straight above the paper and keep your shadow off the page.
- Crop tightly. Open Image Resize & Crop, go to the Crop tab, keep the ratio on Free and drag the box close around the signature. Leave a small white margin. Apply the crop and download.
- Set the pixel size if the form gives one. In Compress Image to KB, open "Set custom dimensions" and type the width and height, for example 140 and 60.
- Choose JPEG and type a target. Pick a number inside the range, not on the edge. For 10 to 20 KB, try 18 KB.
- Compress and check. Compare the preview with your original. The strokes should be dark and smooth, and the background white.
- Download and check the size in your file manager before you upload.
Why signature uploads get rejected
- Wrong size: above the maximum or below the minimum KB.
- Wrong format: PNG or HEIC where the form asks for JPG.
- Grey or shadowy background: usually from a photo taken in poor light.
- Too much empty space: the signature looks tiny once the portal shows it.
- Wrong style: capital letters where running handwriting is required, or the wrong ink colour.
If the file is too small or too large
Too large: lower the KB target or the pixel size a little. A tight crop helps most, because empty white space still costs bytes.
Too small: some forms reject files under a minimum such as 10 KB. In Compress Image to KB, switch to "Adjust quality" and raise the quality, or use slightly larger dimensions if the form allows them. Always start again from your original photo.
Your photo, too
The photo usually has a different size range from the signature. Use the same tool with the photo's numbers, or follow the guide to compressing an image under 100 KB, 50 KB or 200 KB. Some exams now capture the photo live during the application instead of asking for an upload, so read the notification first.
Good to know
Your signature photo is processed in your browser and is not uploaded to our servers. Keep the original photo in case the form asks for a different size later. This guide covers image files for upload forms. To sign a PDF document itself, use PDF Sign.
Frequently asked questions
How do I get my signature between 10 KB and 20 KB?
Crop it tightly, choose JPEG in Compress Image to KB and type a target inside the range, for example 18 KB. Check the result and download it.
What if my signature file is smaller than the minimum?
Switch to Adjust quality and raise the quality, or use slightly larger pixel dimensions, then compress again from the original photo.
Should I save my signature as JPG or PNG?
Use the format the notification asks for. Most exam and job portals ask for JPG or JPEG.
Can I draw my signature on screen instead of scanning it?
Only if the notification allows it. Many portals ask for a handwritten signature on white paper, scanned or photographed. Follow the instructions of your form.