# What is OCR?

OCR is software that recognises the letters in a picture of text, such as a scan or a photo of a page, and turns them into real text you can search, select and copy.

_Source: https://sharelargefilesfree.com/what-is-ocr · Updated 2026-10-13_

**Quick answer:** OCR is software that recognises the letters in a picture of text, such as a scan or a photo of a page, and turns them into real text you can search, select and copy.

## OCR (Optical character recognition) explained

OCR, or optical character recognition, reads the letters in an image and turns them into text. A scanner or a phone camera only takes a picture of a page: to a computer, a scanned contract is the same as a photo of a cat. You can't search it with Ctrl+F, select a sentence or copy a figure. OCR fixes that.

The result comes in two common forms. A **searchable PDF** keeps the original page images and adds an invisible layer of text behind them, so the document looks the same but search and copy work. **Plain text** gives you only the words, ready to edit, translate or paste somewhere else.

Accuracy depends on the scan. Sharp, straight, well-lit pages in a common typeface come out nearly perfect; handwriting, faint photocopies, skewed photos and unusual fonts cause mistakes, so check names and numbers before relying on them.

## How to get a good OCR result

- **Scan at 300 dpi** or take the photo square-on in good light. Blurry or very small text is the main cause of errors.
- **Pick the right language.** OCR uses a dictionary and alphabet for each language; the wrong one turns accents and letters into nonsense.
- **Rotate pages upright** first if they were scanned sideways.
- **Keep the original.** A searchable PDF still contains the page images, so nothing is lost if a word was misread.

## OCR, PDF to text and PDF to Word

| You have | You want | Use |
| --- | --- | --- |
| A scanned PDF or photo | Search and copy, same look | OCR to a searchable PDF |
| A scanned PDF or photo | Just the words | OCR to text (image to text) |
| A PDF made from a document (text already selectable) | The words | PDF to text, no OCR needed |
| A PDF with selectable text | An editable document | PDF to Word |

Quick test: if you can select a word in the PDF, it already has text and doesn't need OCR.

## Frequently asked questions

### What does OCR stand for?

Optical character recognition: software that recognises letters in an image and turns them into text.

### Can I OCR a PDF for free without uploading it?

Yes. Our OCR PDF tool runs the open-source Tesseract engine in your browser, in 19 languages, so the PDF stays on your device.

### Does OCR read handwriting?

Only poorly. OCR is built for printed text; neat block capitals sometimes work, joined-up handwriting usually does not.

### Does OCR change how my PDF looks?

Not when you make a searchable PDF: the original page images stay and an invisible text layer is added behind them.