Tesseract OCR — The Complete Guide: The Open OCR Engine for Turning Scans Into Text
Tesseract OCR is an open-source (Apache-2.0) optical character recognition engine based on a neural network. You may already be using it without knowing — it is the engine behind OCRmyPDF, NormCap and other tools.
Tesseract OCR
Tesseract OCR project
The open OCR engine behind many tools — turns scans into text in more than 100 languages.
Get it from the vendorWhat you get
- More than 100 languages — including mixed languages in one document.
- Input — PNG, JPEG and TIFF images.
- Outputs — plain text, searchable PDF, hOCR, TSV and more.
- Training — can be trained for new fonts and languages.
- Library — embed it in scripts and other programs.
How to use it
It is a command-line tool and library with no graphical interface. On Windows a ready installer is provided by UB Mannheim. Engineers use it to batch-convert old scans to text — for example a short Python loop over a folder of images.
Related tools
To add a text layer to scanned PDFs — OCRmyPDF. To capture text from the screen — NormCap. For a graphical front end — gImageReader.
OCRmyPDF
OCRmyPDF project
Adds a searchable text layer to scanned PDFs — old reports, standards and drawings become searchable.
Get it from the vendor
NormCap
dynobo
A screenshot tool that captures text instead of images — mark an area and the text goes to the clipboard.
Get it from the vendor
gImageReader
gImageReader project
Graphical OCR built on Tesseract — turn scanned pages and PDFs into text or a searchable PDF.
Get it from the vendor
Python
Python Software Foundation
The language behind most modern engineering computation, and its full ecosystem.
Get it from the vendorThe bottom line
Tesseract is the building block of free OCR. For everyday tasks use a tool that wraps it; for automation, work with it directly.