✓
Tool
Category
Pricing
Free?
Updated
CORE
AI Research
Free
✓
Mar 2026
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World's largest open access paper aggregator with 250M+ records and text mining API.
Best for: open-access
Unpaywall
AI Research
Free
✓
Mar 2026
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Free browser extension that finds legal open access versions of paywalled papers.
Best for: open-access
Kopernio
AI Research
Free
✓
Mar 2026
→
Clarivate browser extension for one-click PDF access to research papers via library links.
Best for: browser-extension
BASE Search
AI Research
Free
✓
Mar 2026
→
Academic search engine indexing 300M+ open access documents from 10,000+ providers.
Best for: research
Semantic Scholar ✓
AI Research
Free
✓
Mar 2026
→
Free AI academic search with 200M+ papers, TLDR summaries, and citation graphs.
Best for: research
ReadCube Papers
AI Research
Freemium
✓
Mar 2026
→
Modern reference manager with enhanced PDF reader, AI recommendations, and cloud sync.
Best for: reference-manager