Resize Signature Image
Turn a photo of your signature into a clean, small file that fits an application form. The tool trims the empty margins, whitens the paper, darkens the ink and resizes to your pixels and KB limit.
🔒 Runs in your browser. Your files and text are not uploaded.
How to use the Resize Signature Image
- Sign with a dark pen on plain white paper. Photograph it in daylight from directly above, or scan it, and drop the picture on the box.
- Pick a size from the menu, such as 140 × 60 px, or choose “Custom” and type the width and height your form lists.
- Set “Max size (KB)”, for example 20. Leave “Trim empty margins” and “Whiten the paper and darken the ink” ticked unless the signature is faint.
- Check the result row for the pixel size and file size, then download the JPEG.
How to take a good signature photo
A clean source does more than any setting. Use a fresh sheet of white paper and a pen with dark, solid ink, black or dark blue; a felt tip or gel pen is better than a ballpoint that skips. Sign in the middle, large enough to fill roughly half of the sheet’s width, and photograph it in even daylight with the phone parallel to the paper. Avoid your own shadow, a desk lamp glare and a creased page.
What the tool does to your picture
- Trim empty margins. It finds the dark strokes, crops closely around them with a small border and leaves the rest of the page out, so the signature uses the whole frame.
- Whiten the paper and darken the ink. It evens out the lighting, turns the grey paper white and makes the strokes darker. A clean white background also compresses to a tiny number of bytes.
- Resize to your pixels. The signature is fitted inside the width and height you choose without stretching it, on a white background.
- Fit the file size. The tool lowers the JPEG quality, if necessary, until the file is under your limit.
The result is always a JPEG on a white background, which is what almost every portal that asks for a signature expects.
Common signature sizes
| Size | Ratio | Typical file size |
|---|---|---|
| 140 × 60 px | 7:3 | About 2–6 KB, the classic size for application forms |
| 200 × 80 px | 5:2 | About 3–8 KB |
| 256 × 128 px | 2:1 | About 4–10 KB |
| 300 × 100 px | 3:1 | About 4–12 KB |
These are the dimensions that appear most often, but every portal sets its own, so follow your form. If it states a limit in kilobytes only, such as 20 KB, a larger size with a high quality usually works.
If the result looks wrong
- Strokes look broken or too light. Untick “Whiten the paper and darken the ink”, or retake the picture with a darker pen.
- A grey shadow remains. Retake the photo with even light, or crop the shadow away with the crop tool first.
- The form wants a minimum size as well. Raise a very small file with Increase Image Size in KB.
- The form also wants a passport photo. Use Compress Image to 50 KB or the Passport Photo Maker.
Frequently asked questions
What size should a signature image be?
Follow your form. 140 × 60 pixels and under 20 KB is a very common request, but 200 × 80, 256 × 128 and 300 × 100 also appear. If only kilobytes are specified, anything under the limit that is clearly legible works.
Can I use a signature with a transparent background?
The output is a JPEG on white, which has no transparency. If you need a PNG with a transparent background for documents, ask the recipient: most forms want white.
Is my signature uploaded or stored?
No. The picture is processed in your browser and never leaves your device, which matters for something this personal.
Should I sign a different way for forms?
Sign exactly as you do on your official documents. The portal or institution may compare it with other records, so a signature that looks very different can cause trouble.
Does it work with a photo taken on a phone?
Yes, phone photos work well when taken in daylight from straight above. The tool removes the grey cast and crops the margins automatically.