Free · No upload · Runs on your device

Resize a signature image

Crop, resize and clean up a photo of your signature for online forms. Choose exact pixels, a white or transparent background and a KB limit.

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How to make a clean signature file

  1. Sign with a dark pen on plain white paper and take a well-lit photo or scan.
  2. Enter the width and height the form asks for (300 × 100 px is a common size if none is given).
  3. Choose a white JPG or a transparent PNG, and optionally a maximum size in KB.
  4. Select Make signature file.

What the tool does

It finds the dark ink on the page, trims the empty paper around it, adds a small margin and fits the signature into your chosen dimensions without stretching it. The transparent option fades the paper to clear and keeps the ink, which is useful for placing a signature on a document. If you set a KB limit, JPG quality is reduced only as much as needed.

Privacy matters for signatures

A signature is sensitive. FileKivo processes it entirely in your browser; the image is never uploaded or stored. Close the tab when you are done and the working copy is gone.

Important

Only use a signature image where the organisation allows one. Some forms require a handwritten or a specific digital signature process instead. For photos of other documents, see Compress an image or Images to PDF.

Questions

Why is my signature not detected?
The tool looks for dark ink. Use a darker pen, brighter light and plain white paper.
What size should a signature be?
Use the dimensions stated by the form. If none are given, 300 × 100 px is a sensible start.
Is my signature uploaded?
No. It is processed only in your browser.

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