Liner

What is Liner?

Liner is a research and productivity platform built for professionals, students, and academics who need to find, organize, and synthesize information efficiently. It offers three core product pillars: an accurate cited-answer search engine for everyday queries, Liner Scholar for academic literature review and paper discovery, and Liner Write for drafting professional documents — all within a single interface. Users can highlight and save passages from web pages, PDFs, and YouTube videos into a personal knowledge base, then leverage AI agents to generate literature reviews, research reports, or polished drafts from those saved materials. Liner supports multiple frontier AI models on paid tiers and is trusted by over 13 million users worldwide.

Key Features

• Cited AI Search

  Returns synthesized answers to queries with inline citations from credible web and academic sources, allowing users to verify every claim with one click.

• Liner Scholar

  Dedicated academic research agent for literature review, paper discovery, research gap analysis, and building annotated bibliographies from saved highlights.

• Deep Research

  Multi-step research agent that breaks complex questions into sub-queries, searches across multiple sources, and returns a comprehensive structured report.

• Web & PDF Highlighter

  Browser extension and mobile app that lets users highlight and save passages from any webpage, PDF, or YouTube video into a persistent, searchable personal library.

• Liner Write

  Professional writing assistant that drafts emails, reports, newsletters, and more — with the ability to reference saved highlights and embed citations directly.

• File Upload & PDF Chat

  Upload documents up to 200 MB, ask questions, extract key quotes, and get summaries without manually skimming through dense material.

Use Cases

• Academic Literature Review : Graduate students and researchers can highlight papers, save them to topic collections, and have Liner Scholar synthesize a literature review with proper citations in minutes.
• Professional Research & Briefings : Consultants and analysts can use Deep Research and the highlighter to build comprehensive briefings from large volumes of source material across multiple projects.
• Fact-Checked Content Writing : Content creators and marketers can search with cited sources and draft verified articles or reports using Liner Write without switching between tools.
• Thesis & Academic Paper Writing : PhD candidates can track relevant papers, identify research gaps, and generate structured drafts with supporting citations pulled directly from their saved highlight library.
• Daily Knowledge Work : Product managers, strategists, and knowledge workers can get accurate answers to complex questions and save key insights to a personal library for future reference.

FAQs