Does LanguageTool train AI on your data?
No
“Learneo does not use inputs from any LanguageTool user (Individual or Team Plan) to train its language algorithms or models. This is a default setting in LanguageTool that does not require an opt-out or any action by the user.”
From LanguageTool's privacy policy , checked Oct 28, 2026. In Grammar & Proofreading, 3 of 4 tools whose policies answer this say they don't train on customer content.
The rest of the data policy
Data retention
Not stated
Where data is stored
Not stated
Security and compliance
Other tools that say they don't train on your data
Hemingway Editor“We and our AI providers do not use this content to train, fine-tune, or improve AI models.”
ProWritingAid“When using ProWritingAid, your texts will not be used to improve the quality of our services.”
LanguageTool and your data: common questions
Does LanguageTool use my data to train AI?
No. LanguageTool's policy says: "Learneo does not use inputs from any LanguageTool user (Individual or Team Plan) to train its language algorithms or models. This is a default setting in LanguageTool that does not require an opt-out or any action by the user." (checked Oct 28, 2026).
What security certifications does LanguageTool have?
Its security pages list GDPR.
Which grammar & proofreading tools don't train on your data?
Among the closest alternatives, Hemingway Editor, ProWritingAid say in their policies that they don't use customer content for training.
Business plans often carry different terms than free and individual plans. We record what the public policy says; the quote shows which plan it covers. See LanguageTool's full profile or how other AI tools compare.