Thumbmark maker

Turn a photo of your thumbprint into a clean PNG, or a JPG for upload forms.

Free, no sign-up. It runs inside your browser: your files never leave your device.

Make a clean thumbmark (thumb impression) from a photo of your inked thumb. Get a clear PNG to place on documents, or a small JPG for online forms.

How to use Thumbmark maker

Ink your thumb, press it on white paper and take a photo in good light.
Drop the photo (JPG or PNG) on the page.
Move the Sensitivity slider until the ridges look right, and pick the ink colour.
Choose "PNG, clear" or "JPG on white", and a size limit if the form has one.
Click "Make thumbmark" and download it.

"PNG, clear" has a transparent background and drops onto any page or form. "JPG on white" is for upload forms that only take JPG.

Yes. Under "Keep it under", choose 20 KB, 50 KB or 100 KB.

Keep "Remove specks" on. It clears dust and paper grain around the print.

No. The photo is processed on your device and is never sent anywhere.

Edit PDF: Click any text to change it, add text and images.
Sign PDF: Draw, type or photograph your signature and place it.
PDF to handwriting: Turn a PDF's text into realistic handwritten pages.
Text to handwriting: Type text and get handwritten notes as a PDF.
Handwriting to PDF: Convert handwritten pages to typed, searchable text.
Fill PDF form: Fill a form and lock the answers so everyone sees them.
Redact PDF: Permanently delete words and phrases from the file, not just cover them.
Add watermark: Stamp text like DRAFT or CONFIDENTIAL, or your logo, across your pages.
Add page numbers: Number pages with your own format and position.
Bates numbering: Stamp sequential Bates numbers across many files.
Headers & footers: Add text, dates and page numbers to every page.
Flatten PDF: Make forms and annotations part of the page for good.
Invert colours: Invert, dark mode, sepia or grayscale versions of a PDF.