Home / Compare / CORE vs Unpaywall

CORE vs Unpaywall

AI Research tools comparison · Updated 2026

Choosing between CORE and Unpaywall? Both are popular AI Research tools. CORE is free to use and focuses on 250M+ metadata records. Unpaywall is free to use and specializes in Browser extension. Here's a detailed side-by-side comparison to help you decide.

At a Glance

CORE Unpaywall
Category AI Research AI Research
Pricing free free
Starting Price Free Free
Best For open-access, research, text-mining open-access, browser-extension, free
Features 6 listed 6 listed

CORE

World's largest open access paper aggregator with 250M+ records and text mining API.

AI Research free
VS

Unpaywall

Free browser extension that finds legal open access versions of paywalled papers.

AI Research free

Feature Comparison

CORE Unpaywall
250M+ metadata records Browser extension
Full-text access Open access detection
Open access aggregation 50,000+ source repositories
API for text mining DOI-based lookup
Dataset services Green lock indicator
Repository dashboard API access

Pricing Comparison

CORE

free

Free for individuals. API access free for research. Commercial API licensing available.

Unpaywall

free

Completely free browser extension. Data feed available for institutions.

Pros & Cons

CORE

Pros
  • + Largest open access collection
  • + Full-text availability
  • + Free API for research
  • + Great for text mining
Cons
  • Interface not very modern
  • Duplicate records possible
  • Search relevance can be poor
  • Full-text not always available

Unpaywall

Pros
  • + Completely free
  • + Works automatically while browsing
  • + Legal open access only
  • + Simple one-click access
Cons
  • Only finds already-open papers
  • Not all papers have OA versions
  • Browser extension only
  • No search functionality

The Verdict

Both CORE and Unpaywall are strong AI Research tools. CORE stands out for Largest open access collection, making it ideal if that's your priority. Unpaywall excels at Completely free, which may be more important for your workflow.

Related Topics

Also Consider

Other popular AI Research tools you might want to compare.

More Comparisons & Alternatives