Tesseract
Thirty years old, Apache-2.0, and it runs absolutely everywhere.
Tesseract is the OCR engine most of the world's text extraction has quietly gone through, originally from HP, developed by Google for a decade, and Apache-2.0 throughout. It recognises over a hundred languages, has bindings for every language you might be writing in, and is packaged in every Linux distribution. Modern neural extractors beat it on complex layouts, but on clean scanned text it is fast, dependable and effectively free of dependencies — often the right tool precisely because it is boring.
What it does well
- +Over a hundred languages, bindings for everything
- +Extremely mature and stable — decades of production use
- +Packaged everywhere; trivial to install and deploy
- +Apache-2.0 with no dependency weight
Where it falls short
- −Weak on complex layouts, multi-column pages and tables
- −Needs image pre-processing for good results on poor scans
- −No document understanding — it gives you text, not structure
Tesseract as an alternative to
Where Tesseract shows up in our comparisons, and how it ranked.
Tesseract head-to-head
Straight comparisons against the tools people weigh it against.