How to use OCR PDF
- 1
Pick a scanned PDF, such as a document from a scanner or the Scan to PDF tool.
- 2
Choose the language of the document. Keep "Skip pages that already have text" ticked for documents that mix scans and normal pages.
- 3
Press "Make searchable". Our server reads the pages one by one, a few seconds each.
- 4
Download the searchable PDF, or copy the recognised text from the preview.
What this tool does
OCR PDF makes scanned documents searchable. It reads the text on each scanned page with the open-source Tesseract OCR engine and adds that text to the PDF as an invisible layer, lined up with the words on the page.
Features
- Searchable and copyable: use Ctrl+F in any PDF reader, select words and copy them.
- The pages look unchanged: the text layer is invisible, on top of the original scan.
- Six languages: English, Spanish, French, German, Portuguese and Indonesian.
- Mixed documents: pages that already have real text can be skipped.
- Text preview with a copy button, for when you only need the words.
- Fast on any device: the pages are read on our server at 300 dpi.
Limits
- Six languages for now, one per document.
- Handwriting, very small text, tables and photos taken at an angle are read less reliably.
- Letters the built-in PDF font can't show, such as those outside Western European alphabets, are left out of the text layer.
- Large documents take a while, because the pages are read one after another.
- Password-protected PDFs need to be unlocked first.
Where your PDF is processed
The text is recognised on our own server, with Tesseract running there rather than at an outside OCR service. Your PDF is sent over an encrypted connection. Once the pages are read, the uploaded file is deleted. The searchable copy follows when its 15-minute download window ends, so nothing is left after an hour, and "Delete from our server now" removes it at once. We don't log file names or the recognised text.
Frequently asked questions
What does OCR do?
OCR (optical character recognition) reads the letters in a picture of a page. This tool puts the words it reads into the PDF as an invisible layer on top of the scan, so the page looks exactly the same, but you can search it, select text and copy it.
How accurate is it?
Clean, straight scans of printed text at a normal size are usually read almost perfectly. Handwriting, very small or faded print, unusual fonts, photos taken at an angle and complex tables give more mistakes. Check important numbers before you rely on them.
Which languages are supported?
English, Spanish, French, German, Portuguese and Indonesian. Choose the document's language before you start, because each language has its own model that knows which words and accents to expect.
How many PDFs can I make searchable?
Without an account you can run OCR on 10 PDFs a day, and on 30 with a free account. Each PDF can be up to 25 MB, or 50 MB when you are signed in.
Where is my PDF processed?
On our server. The PDF travels over an encrypted connection and is deleted automatically, the upload as soon as it is read and everything within 1 hour. You can also delete it yourself straight away.