OmniDocConvert Scanned PDF to Text with OCR
Learn how to run OCR on a scanned PDF so you can select and copy its text, then check the result before you reuse it.
A scanned PDF looks like a document, but it is usually a picture of one. You can read the page, yet you cannot select a word, search for a phrase or copy a paragraph into an email. Old reports, signed contracts and photographed handouts often arrive this way. If you need the words themselves, you have to recognize the text first.
This guide is for anyone who wants plain, copyable text from a scan and does not need the original layout rebuilt. It explains how to convert a scanned PDF document into text with optical character recognition (OCR), which reads the characters on each page and adds them as selectable text behind the page image.
You will learn how to confirm that a file needs OCR, how to run it in the OmniDoc desktop PDF editor, and how to check the output before you reuse it.
How to convert a scanned PDF document into text? The short answer
Run OCR on the scanned PDF so each page gets a selectable text layer, then copy the text you need and check it against the original page.
| Your situation | What to do | Why |
|---|---|---|
| You only need the words, with no formatting | Run OCR in the desktop PDF editor, then copy the text | Plain text is the goal, so no export step is needed |
| You want an editable file with headings and tables to rework | Run OCR, then export to Word | Word gives you a document you can restructure |
| The text must go into a plain .txt file | Copy the recognized text into a plain text editor and save as .txt | Plain text drops all formatting and opens in almost any tool |
| Selecting a line of text already works | Skip OCR and copy directly | The PDF already has a text layer, so OCR adds little |
| You plan to translate the document afterward | Run OCR first, then review the text before translating | You can confirm the source words before any translation step |
Before you start
Take a few minutes to check these points. Each one saves time later.
- Confirm the file is actually scanned. Try selecting a line of text. If the selection highlights words, the PDF already has text and you may not need OCR. If nothing can be selected, the pages are most likely images.
- Keep an untouched copy of the scan. Work on a duplicate so you can compare against the original and start over if the recognition goes wrong.
- Look at scan quality. Blurry, skewed or low-contrast pages are harder to recognize. If the text looks faint or tilted on screen, a sharper rescan will usually give cleaner output.
- Check the language and special characters. Confirm that the printed text is in the language you expect. Pages with mixed languages, unusual symbols or handwritten notes need a closer check afterward.
- Install the desktop client. OCR is part of the OmniDoc desktop PDF editor, so download the client for Windows, macOS or Linux from download.omnidoc.top before you begin.
Running OCR on a scanned PDF in OmniDoc, step by step
- Open the desktop client and the PDF editor. The OCR feature lives in the PDF editor, so start there rather than in the document editor.
- Open your scanned PDF. Use a copy of the file, not the only version you have, so the original stays unchanged.
- Run OCR on the file. OCR analyzes each page image, recognizes the characters and adds a text layer. The page should look the same as before, but its words can now be selected.
- Wait for processing to finish before you edit. Interrupting recognition can leave some pages with partial text, so let the file complete the whole pass.
- Select a paragraph to confirm the result. If you can highlight the words and the highlight follows the line, the text layer is working. If you can't, check the scan quality and try again.
- Copy the text you need. Select a section, copy it and paste it into a plain text editor if you want a clean .txt file. Plain text carries no fonts or colors, which makes it easy to reuse.
- Export to Word if you need an editable file. Choose this only when you plan to rework headings, tables or paragraphs. Do not expect the output to match the scan exactly; treat it as a starting point.
- Save the result and keep the original scan. Name the new text file clearly, such as with the document title and the date, so you can tell it apart from the source.
Check the result
Machine recognition does not guarantee accuracy, so review the output before you rely on it. Focus first on numbers, names and dates, since a single wrong digit can change the meaning.
| Check | How to see it | If it's wrong |
|---|---|---|
| Characters and words | Read the copied text next to the page image, paragraph by paragraph | Edit the paragraph text in the PDF editor or retype the word |
| Numbers, dates and currency | Compare every figure with the scan, one at a time | Correct it by hand and recheck the same line on the original |
| Line breaks and hyphens | Paste into a plain text editor and look at the ends of lines | Join split words and remove stray breaks manually |
| Missing text | Scroll through every page and compare the page count with the scan | Run OCR again on that page; if text is still missing, rescan the page |
| Multi-column pages | Check whether lines from different columns have been mixed together | Copy each column separately and join them in order |
| Known phrase test | Search the output for a phrase you can see on the page | If it isn't found, the recognition missed or changed it; review that section |
Work through long documents in sections. Checking one section at a time is easier than reviewing everything at once, and it helps you spot patterns, such as a recurring symbol that is consistently misread.
❓ FAQ
1. Does OCR change how the PDF looks?
No. OCR adds a selectable text layer to each page, and the page image stays as it was. Any visible change would come from editing the text afterward, not from recognition itself.
2. Can I photograph the pages and paste them into a general-purpose chatbot instead?
You can try, but chatbots may paraphrase, skip or reorder text, and they do not show you a text layer that lines up with the page. Use a dedicated OCR step for source-faithful text, then check every page against the scan.
3. Why does my copied text contain odd characters?
Usually the scan is low contrast, skewed, or uses an unusual font or symbol set. Compare the affected line with the page image, correct the characters by hand, and rescan the page if the problem repeats across the document.
4. Do I need to translate the text after OCR?
No, translation is a separate choice. If you do want it, OmniDoc's translation accepts scanned PDFs as they are, so you can run OCR for copyable text or upload the scan for translation depending on your goal.
📝 Summary
To convert a scanned PDF document into text, run OCR in the desktop PDF editor, copy the recognized text and check it against the original scan. Export to Word only when you need an editable layout, and always verify numbers and names before you reuse the output.
