Overview
Liner AI — Your AI research co-pilot
Liner is a web highlighter and AI research assistant used by over 8 million users. It lets you highlight text on any webpage or PDF, then uses AI to summarize, explain and cross-reference your saved highlights into a searchable knowledge base.
Web & PDF highlighting
AI summarization of highlights
Personal knowledge base
Chrome & Safari extensions
Features & capabilities
Everything it does, in plain English.
The honest take
Where it shines, where it stumbles.
✓ Pros
- ✓8M+ users
- ✓Works on any website
- ✓Free tier is generous
! Watch-outs
- !AI features require premium
- !Mobile app less capable
Who it's for
Where Liner AI pays for itself fast.
Academic research
Content curation
Studying
Competitive research
Community reviews
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