How to make a scanned PDF searchable with OCR
Updated 4 min readBy Total PDF Tools
Quick answer
To make a scanned PDF searchable, open OCR PDF, add the file and run recognition. The tool reads the text in each page image with Tesseract and adds an invisible text layer on top, so the PDF looks exactly the same but you can search, select and copy the words. You can download the searchable PDF, a plain .txt file, or both. Processing runs in your browser.
Open OCR PDFStep by step
- 1
Open OCR PDF
Go to the OCR PDF tool and add your scanned PDF or image.
- 2
Choose the output
Pick a searchable PDF, plain text, or Both.
- 3
Run OCR
Start recognition. The OCR engine downloads the first time you use it, then each page is processed on your device. Pages that already contain text are skipped.
- 4
Download
Save the searchable PDF and/or the text file.
How to get accurate OCR results
OCR accuracy depends mostly on the scan:
- Scan at 200–300 DPI. Lower resolutions make small letters hard to read.
- Keep pages straight. Photographed at an angle? Straighten them with Scan to PDF first.
- Use good, even lighting and avoid shadows across the text.
- Black & White scans of printed text usually give the best results.
How do I know if a PDF needs OCR?
Try to select a word or search for it with Ctrl+F (Cmd+F on a Mac). If you can't select text or search finds nothing, the page is an image and needs OCR. PDF to Text also detects pages without a text layer and points you to OCR.
Frequently asked questions
Which languages does the OCR support?
The website's OCR currently uses English language data. Other Latin-script text is often partly recognised, but accuracy is best for English.
Does OCR change how the PDF looks?
No. The recognised text is added as an invisible layer behind the page image, so the document looks exactly the same.
Can OCR read handwriting?
OCR is designed for printed text. Neat handwriting may be partly recognised, but results are unreliable.