How to Edit a Scanned PDF on Mac

A scanner or a phone scanning app saves each page as an image. The letters you see are pixels, so a PDF editor finds no characters to select or change, unlike in a PDF made on a computer, which holds real text.

Editing a scan therefore needs one extra step: the page has to be read with text recognition (OCR) to find where each line sits and what it says. Everything below depends on that step.

Preview can't change the words in a scan, but it can put new things on top of the page, and Live Text lets you select the text in a scanned page and copy it. That is handy for one phone number or one paragraph.

A white shape or a text box laid over a mistake only hides it; the scan underneath stays as it was. To actually change the words, the editor has to read the page first.

• Copy text: with Live Text, drag across the words in the scanned page and press Command-C.
• Add text: choose Tools > Annotate > Text, type in the box and drag it into place.
• Sign: choose Tools > Annotate > Signature and create a signature with the trackpad or the camera.

File Acture's Edit & Sign PDF opens the PDF in an editor. When a page has no text you can select (a scan, a document printed to PDF with its words drawn as shapes, or a page with only an invisible OCR layer), the editor reads the page with the text recognition built into macOS (Vision) as soon as you open it. Each page is read once, and nothing leaves your Mac. For a PDF made on a computer, see how to edit text in a PDF on Mac.

While it reads, a card in the middle of the page says Preparing this page for editing (OCR) and an orange bar above the page says the page is being read. The first page can take up to a minute, and Add Text, Signature and the other tools keep working meanwhile. Then the bar says OCR has finished and reminds you to check the text before saving.

Double-click a word or triple-click a line to select it, or turn on Edit Text and one click places the cursor. Type the correction and press Return to keep it, or Esc to cancel; Command-Z undoes it.

Editing a scan is only as good as the reading of the page, so a sharp, upright scan gives the cleanest result.

• Check the whole line. Saving redraws the entire line you edited, not only the words you changed, so a letter the reading got wrong elsewhere in that line is redrawn wrong.
• Use a straight, sharp scan. A line tilted by more than about 1.5 degrees, or sitting on a photo or a patterned background, is not offered for editing. Rescan the page straight if you can.
• Turned pages are not read. A page stored rotated is left alone, and the bar then says its words are drawn as shapes or a picture. Use the Eraser to remove them and Add Text to type new ones.
• Many changes? If a page needs more than a few edits, convert the scanned PDF to Word and edit it there.
• Want it searchable instead? OCR PDF adds a text layer to the whole scan. You do not need to run it before editing: the editor reads the page itself.

Online PDF editors work on a copy of your document on their servers, which is a poor fit for scans of contracts, bank statements and ID documents. File Acture reads and edits the PDF on your Mac and never uploads it. To count free runs it sends only the tool's name, the app version and anonymous identifiers, never file names or contents.

The free version includes 3 runs on each Mac, and saving an edited PDF counts as one run; for unlimited use, see pricing. Pro is a one-time purchase, and one license activates one device.