Glasp
Glasp
Social highlighting for web, PDFs, YouTube, and Kindle — unlimited free public highlights; Pro $12.50/month.
Research & Reference
Other checked tools in the same category as Semantic Scholar — each with a genuine free tier, verified against the provider's own pages, and described with its honest limits.
Best for: weighing Semantic Scholar against free rivals before committing time or money to one.
Glasp
Social highlighting for web, PDFs, YouTube, and Kindle — unlimited free public highlights; Pro $12.50/month.
PDF.ai
Chat with PDFs plus a parse/extract/split API — plans exist; public pricing not shown at check time.
AskYourPDF
Chat with PDFs and documents — 50 free questions a day; Premium from $11.99/month.
Readwise
Resurfaces highlights from Kindle and 40+ sources, with an AI-powered read-it-later reader — 30-day trial, from $5.59/month.
Wolfram
Expert-level computed answers across math, science, and life — free basic access, Pro for steps and heavy use.
ChatDOC
Chat with PDFs with cited sources — 100 questions free, no card, 10 uploads a day.
Consensus
AI search over 400M peer-reviewed papers with a Consensus Meter showing scientific agreement — free tier confirmed at $0.
Humata
Chat with your PDFs — free plan covers 60 pages a month, no card required.
Elicit
The AI research assistant for literature — search 138 million papers, screen them, and extract data into tables. Free plan with unlimited search and summaries.
LMArena
Chat with frontier AI models side by side and vote on the better answer — free, no account needed, from the project behind the influential LMSYS leaderboards.
A free platform for data science and machine learning — public datasets, browser notebooks with free GPUs/TPUs, competitions, a model hub, and hands-on courses, at kaggle.com.
Google's AI research and note-taking tool that answers from the sources you upload — documents, PDFs, slides, links — and cites them. Free at notebooklm.google with a Google account, it can even turn your sources into a spoken audio overview.
Perplexity AI
An answer engine that responds to questions in plain language and cites its sources — free to use at perplexity.ai, with a paid Pro plan for more powerful models and higher limits on its deeper research modes.
Semantic Scholar alternatives are usually explored when a researcher needs different corpus coverage, wants full-text PDF access the index cannot provide, or needs AI-assisted reading features on top of a citation graph.
Worth comparing before you switch:
Stay put if: The citation graph and free API are Semantic Scholar's unique strengths — literature-review tooling built on it is hard to replace like for like.
Back to the Semantic Scholar listing or every checked tool in Research & Reference.