What is Liner?

Content last verified May 4, 2026 · by the AI Tools Set Research Team

Liner is an AI search and research assistant that answers questions using vetted, trustworthy sources and helps you highlight, organize, and cite what you find. It grew from a popular web highlighter into a full research copilot.

With source filtering, citations, and knowledge organization, it targets students and professionals who want reliable answers and a way to keep track of their research.

Key Features of Liner

Trusted-source answers: Prioritizes credible sources.
Web highlighter: Save and organize highlights across the web.
Citations: Generate references for your research.
Research spaces: Organize findings by project.

Use Cases for Liner

Research with trusted sources
Highlight and save findings
Write with citations
Organize study material
Summarize documents

Pros & Cons

Pros

✓

Focus on credible sources

✓

Great highlighting tools

✓

Good for students

✓

Citation support

Cons

✗

Best features need Pro

✗

Overlaps with note apps

Pricing

Free

$0 /mo

✓Limited AI searches

✓Highlighter

✓Basic citations