How to Resize a Signature for Online Forms
Last updated: 2026-10-30
From pen and paper to a clean, correctly sized signature image that upload forms accept.
Capture a clean signature
- Sign on plain white paper with a black or dark blue pen. A gel pen or thin marker photographs better than a light ballpoint.
- Sign a little larger than usual so the strokes stay visible after resizing.
- Photograph from directly above in daylight, with no shadow from your phone or hand. A scanner works even better.
Crop and resize
- Open the Image Cropper and crop closely around the signature, leaving a small margin. Use the "Free" shape unless your form specifies a ratio.
- Download the cropped image and open it in the Signature Resizer.
- Enter the width, height and maximum KB from your form's instructions.
- Turn on "Whiten background" so grey paper becomes pure white. Raise the strength until the background is clean, but stop before thin strokes start to fade.
- Click Resize signature, check the preview, and download.
Getting the proportions right
Signatures are usually much wider than they are tall. If the form's box is a different shape from your signature, crop with a little extra white space above and below (or on the sides) so that the final resize does not squash your signature.
Always use the exact dimensions in the official notification. The sizes shown in CentralMirror are common examples, not requirements of any specific organisation.