What it does
Scan to PDF turns a photo of paper into a flat, tidy page. You take a picture with your phone camera (or add pictures you already have), the tool looks for the page edges, and you can drag four corners to fix them. It then straightens the page as if you had looked at it from straight above, and cleans up the shadows.
Add as many pages as you need and save them as one PDF. Everything runs in your browser; the pictures are never uploaded. After saving, shrink the file with file compressor, reorder pages with organise PDF, or change formats with file converter.
How to use it
- Press Take a photo on a phone, or Add images to pick files. Put the page on a darker table for the best edge finding.
- Drag the four round corners onto the corners of the page. Find page edges tries again by itself; Use whole photo skips straightening.
- Pick a look and a page size. Add more pages the same way; use the arrows to reorder and the cross to delete.
- Press Download PDF.
What each setting does
- Original: keeps the colours as photographed.
- Grey: removes colour, which makes smaller files.
- Black and white: compares each spot with its surroundings, so text stays black even in uneven light.
- Whiten background: lifts shadows and grey paper to white but keeps colour ink and stamps.
- Page size: A4 or Letter put the scan on a standard page with a small margin; Fit the page makes each PDF page the shape of the scan.
- Turn page: rotates the page a quarter turn.
Worked example
You photograph a 2-page rental form on a dark desk. The tool outlines each sheet; you nudge one corner that caught a shadow. Choose Black and white and A4, add the second sheet, and press Download: you get a 2-page A4 PDF.
FAQs
Why are the edges wrong? Edge finding looks for the largest bright shape. A white table or a cluttered background confuses it, so drag the corners by hand.
Why is the file big? Colour photos are large. Choose Grey or Black and white, then use compress-file.
Is the text searchable? No. The PDF holds pictures of the pages, not typed text.
Is it stored anywhere? No. Close the tab and it is gone.
Where the numbers come from
- Page flattening, edge finding and clean-up filters are fibub's own code (homography and local-average thresholding). PDF made with pdf-lib (open source).
Standard scientific values, such as constants, atomic weights and melting points, are facts found in every textbook; we name where ours were checked. If you are an author or publisher and want a value, a credit or a table changed or removed, tell us and we will act quickly.
Last updated 2026-11-10.