How to edit a scanned PDF

▶ 1. Understanding what you have in front of you

A scanned PDF is not a faulty PDF: it is simply a container that holds the image of a page instead of text.

The test is immediate: try selecting a word. If nothing highlights and you find yourself drawing a rectangle, the document is a scan. That is why no editor manages to “correct the typo”: technically, that typo does not exist as text.

The solution therefore starts with a recognition step. With 123 PDF Editor PRO the whole route runs in the browser tab, without installing desktop software and without uploading the document — a relevant point, since scans are often contracts, medical reports or identity documents.

▦ 2. Preparing the pages

Before recognising the text it is worth sorting out the structure: recognition run on crooked or duplicated pages gives mediocre results.

1. Open the file and go into Organize pages.
2. Straighten crooked pages with Rotate left or Rotate right.
3. Delete blank pages and duplicates produced by the scanner.
4. If the margins are huge, trim them with Crop page.
5. Confirm with Apply page changes.

◎ 3. Recognising the text

This is the step that turns the image into a proper document.

1. If the Scanned pages detected window appears, carry on from there; otherwise open Local OCR.
2. Select the language of the document, or leave Automatic if you are not sure.
3. Click Run local OCR and wait for processing to finish.
4. Check on one page that the text is now selectable.

✍️ 4. Correcting the text

After recognition the document is edited like any other PDF, with one caveat: recognised text may contain the odd reading error.

1. Choose Word mode for pinpoint corrections or Text block to rewrite whole sentences.
2. Click the text and correct it; the panel shows the font, size and colour detected.
3. Pay particular attention to numbers, dates, codes and proper names, where recognition errors are most frequent.
4. Use Search and replace if the same error repeats throughout the document.

▧ 5. Images, stamps and signatures

Scans often contain graphic elements that need handling separately from the text.

1. Switch to ▣ Select image mode to select logos, stamps or boxes.
2. Replace an outdated logo with Replace with local image (PNG or JPG).
3. Delete elements that are no longer relevant with Remove image.
4. To add a signature, use Add signature: the procedure is described in the guide on how to sign a PDF.

⤓ 6. Saving and archiving

A scanned and recognised document is worth far more than the original, because it becomes searchable: it deserves to be archived properly.

1. Click Download PDF to save the edited version.
2. Scans are often heavy: if you have to email them, compress them following the guide on how to compress a PDF, keeping the option that preserves selectable text switched on.
3. If the document contains personal data, consider Password protection.
4. Use Save project if the job is long and you want to come back to it later.

? 7. Frequently asked questions

The questions that come up most often on this topic.