Colandr vs Rayyan

Colandr is a free web platform for evidence reviews and other document reviews and syntheses. Machine learning ranks citations by relevance to help screen titles and abstracts, while natural language processing classifies included documents into user-defined categories and assists full-text data extraction. Reviewers retain the final inclusion, exclusion, and classification decisions, and teams can collaborate and cross-check work. Citation files can be imported in TXT, RIS, or BIB formats, with a 40 MB limit per import, and screening decisions and extracted data can be exported as CSV. Colandr does not connect directly to citation databases; users export citations elsewhere, although the platform can help create Boolean search strings. Full-text papers must be found and imported individually, with no mass-upload feature. Relevance rankings update after every 10 screened citations, and metadata suggestions begin after 50 hand-coded extractions. Colandr describes itself as open-source and open-access.

Rayyan is a platform for teams carrying out systematic evidence reviews, with workflows intended to be transparent, auditable, and reproducible. Its process spans reference import, collaboration, deduplication, title and abstract screening, full-text screening, data extraction, risk-of-bias assessment, and reporting. ResearchPilot AI Reviewer screens articles against criteria set by the user and gives decisions with reasoning notes. The Analyzer suggests inclusion or exclusion with justification, while the researcher retains final decision-making. ResearchPilot can also extract answers to custom questions from PDFs and metadata, highlight relevant passages, and let users inspect the answers. References are imported from exported files rather than a direct database connection. The API offers programmatic access to reviews, references, decisions, and metadata, plus workflow automation and external integrations. Rayyan is available on Android, iOS, web, and through an API. The Free plan allows three active reviews and two free reviewers; paid options start at $8.33 a month per seat, billed annually. Free mobile access is limited; Essential and higher provide unlimited mobile access.