Understand what the file represents

A drawn signature PNG is an image of a mark. It can be placed in a document when the recipient accepts that workflow. It does not prove who signed, detect later changes or provide the certificate-backed verification associated with a cryptographic digital signature. Acceptance depends on the document and the receiving organization.

Draw only a signature you are authorized to use. Keep the exported file private, because anyone who obtains a copy may be able to paste the pixels elsewhere. Do not use a public image-sharing link as permanent storage for a signature. If the document requires a particular electronic signing service, follow that process.

Draw at a comfortable size

The drawing area accepts a mouse, touch or pen. Choose a dark ink color and a moderate stroke width. Write at a comfortable scale rather than trying to fit the exact final document size on the canvas. Use Undo stroke to correct one movement; Clear drawing starts a new attempt.

A touchpad can produce uneven curves. Try a slower stroke or a pen-enabled device if one is available. Avoid repeatedly tracing the same line until it becomes a thick blob. The goal is a clean representation of your normal mark, not a large amount of ink.

  1. Draw one complete attempt.
  2. Select transparent or white background deliberately.
  3. Add enough crop padding to keep the outer strokes intact.
  4. Create the PNG and inspect the result.
  5. Download and store it in a location you control.

Check the edges and background

The export crops around the recorded strokes with padding. Inspect the first and last letters, tall strokes and low descenders. If anything touches the image boundary, increase the padding and regenerate. A signature that looks fine on white may show light fringes when placed on a colored page.

PNG supports transparency; JPEG does not. Keep the PNG if the signature should sit directly over a document background. Converting it to JPEG introduces a solid rectangular background and may add compression artifacts around the thin lines. Test the actual document placement before sending the document.

Keep document review separate from image creation

Read the entire document, confirm the recipient and check which fields require signing before placing the image. A signature tool cannot determine whether you should agree to the document. Keep an unmodified copy of the document and a copy of the version you submit.

Reduce the image only as much as needed for the page. Excessive enlargement can make strokes soft, while excessive shrinking can make them disappear. For a high-stakes agreement or an identity-sensitive workflow, use the recipient’s accepted signing method and obtain appropriate advice if needed. Nepocore creates the image locally; it does not send, witness, certify or submit a signed document.

References & method notes

The linked references explain the underlying formats, APIs or methods. Worked examples and instructions are original to this guide; a reference is not an endorsement of Nepocore.