How to signature resizer
- Sign on plain white paper with a black or dark blue pen.
- Photograph it in good light, straight from above, and choose it here.
- Pick the size your form asks for and drag the box around the signature.
- Keep "White background" on and tap Make signature.
Why signature uploads get rejected
The usual reasons are a grey or shadowed background from a phone photo, a signature too small inside a large empty image, or a file over the KB limit. The clean-up option turns the paper pure white and the ink darker. Cropping tightly makes the signature fill the frame, and the KB cap keeps it within limits.
Getting a clear signature
- Use a gel or felt-tip pen; ballpoint lines can look faint once compressed.
- Sign a little larger than usual, about 5–7 cm wide.
- Avoid flash; daylight near a window gives even light.
Form rules differ: always check the exact size and KB range in your form's instructions.
Is it safe to upload my photo?
Your image is never uploaded. ResizeKB processes files inside your own browser using the same technology that draws images on web pages, so the photo never leaves your phone or computer. That matters for documents like passport photos, ID scans and signatures. You can even disconnect from the internet after the page loads and the tool keeps working.
Frequently asked questions
My signature looks too thin after resizing. What can I do?
Sign again with a thicker pen, or choose a larger size preset if your form allows it. Small sizes at low KB lose fine strokes.
Can I make a transparent signature?
Forms almost always ask for JPG, which has no transparency, so this tool gives a white background.
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Last updated 2026-10-27