When a phone photo can stand in for a scanner
Someone wants a signed letter, a receipt or a page of a contract as a PDF, and there is no scanner nearby. A photo taken at an angle shows a slanted page with the table around it. This tool turns that photo back into a flat, square page: you mark the four corners of the paper, and the slant is undone on your device. It also takes a PDF that was scanned crooked and turns its pages straight.
Updated
Which tool you need
Photos of paper taken at an angle, with a desk or a hand in the frame
This tool. Drag each photo's corners onto the corners of the sheet, choose a page size and a clean-up mode, and the pages come out flat and cropped.
A scanned PDF whose pages lean a few degrees
Choose the PDF instead of photos. Each page's lean is measured from its lines of text, and you can change any page's angle before saving.
Screenshots or photos that are already straight and need no corner work
Image to PDF puts them on pages as they are, and it reads HEIC photos where your browser can open them, which this tool does not.
A scan that is straight but gray, colored or too large
PDF to Black and White converts the scanned pictures themselves, to gray or to one bit per pixel, and a mostly scanned file often comes out smaller.
What a corner-flattened photo can and cannot match
Marking the corners undoes perspective: the page that was a trapezoid in the photo becomes a rectangle, and everything outside the sheet is cut away. The corners start at the edges of the photo and are not found for you, so placing them carefully is the step that decides the result.
What it cannot undo is a page that was not flat. A curled receipt or the curve of a book near its spine is treated as if it were a flat sheet, so lines of text there stay bent. Shadows, glare and blur are also in the photo for good; good light from above and a steady hand matter more than anything chosen afterwards.
Color, grayscale or black and white
Color keeps the photo as it was taken, which suits a page with a stamp, a colored form or a photograph on it. Grayscale whitens the paper and darkens the ink, which is usually what makes a phone photo look scanned.
Black and white works like a scanner's text mode and makes the smallest file. It decides black or white from each part of the page's own surroundings, so an unevenly lit photo does not turn one corner dark, but a pale pencil note or a light signature can disappear: check the preview before sending it.
What straightening a scanned PDF changes
Straightening turns what is drawn on each page by up to fifteen degrees either way, without redrawing it, so the scan's own picture is not compressed again. A page whose angle is left at zero is not touched.
Comments, links and form fields sit on top of a page rather than in it, so they stay where they were while the page turns under them. The corners of a turned page can be trimmed slightly, because a tilted rectangle no longer fits the same page exactly.
What to know before you start
- The text is not made searchable: there is no OCR here.
- Photos must be JPEG, PNG or WebP, up to 64 MB each and 200 to a PDF.
- Corners are placed by hand, not detected.
- Password-protected PDFs must be unlocked before they can be straightened.