Direct comparison
SciFinder vs Reaxys Comparison
Compare CAS SciFinder and Elsevier Reaxys: database coverage, reaction workflows, substance indexing, patent data, retrosynthesis tools, and pricing models.
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How do CAS SciFinder, Elsevier Reaxys compare side by side?
The table below compares CAS SciFinder, Elsevier Reaxys across 12 procurement-relevant dimensions, from developer & historical heritage through sources & verification.
Side-by-side comparison
| Dimension | CAS SciFinder | Elsevier Reaxys |
|---|---|---|
| Developer & Historical Heritage | Developed by Chemical Abstracts Service (CAS), a division of the American Chemical Society (ACS). Built upon the comprehensive indexing of Chemical Abstracts since 1907. | Developed by Elsevier. Built on the combined heritage of the Beilstein Handbook of Organic Chemistry, Gmelin Handbook of Inorganic and Organometallic Chemistry, and Patent Chemistry databases. |
| Primary Focus & Architecture | Bibliographic, patent, and substance discovery engine designed for comprehensive literature monitoring across chemistry, biology, materials science, and engineering. | Factual chemical database structured specifically around experimental reaction conditions, yields, catalysts, solvents, and validated physical-chemical properties. |
| Substance Indexing & Registry | Home of the official CAS Registry Number system, indexing over 204 million organic and inorganic substances, alloys, coordination compounds, polymers, and biological sequences. | Indexes over 160 million substances with unique Reaxys IDs, tightly linked to experimental property tables, bioactivity metrics, and reaction pathways. |
| Reaction & Synthesis Workflows | Integrates CASREACT with literature and patents. Provides reaction mapping, transformation filters, and reagent roles with direct links to full-text sources. | Highly structured reaction tables displaying side-by-side yields, temperatures, pressures, solvents, catalysts, and verbatim experimental procedures extracted from literature. |
| Retrosynthetic Analysis Tools | CAS SciFinder Retrosynthesis Planner combines deep neural network algorithms with validated CAS-curated reaction rules to suggest synthetic routes for known and novel targets. | Reaxys Predictive Retrosynthesis leverages machine learning models trained on millions of published synthetic steps to generate multi-step retrosynthetic pathways. |
| Historical Literature Depth | Comprehensive journal and patent coverage from 1907 to the present, with selected historical records dating back into the 19th century. | Unmatched historical depth for organic and inorganic chemistry, indexing literature and experimental properties dating back to 1771 through Beilstein and Gmelin integration. |
| Patent Searching & Prior Art | Exhaustive global patent coverage indexing patents from over 60 patent authorities worldwide, including Markush structure searching and legal status tracking via PatentPak. | Curated patent coverage from major global offices (USPTO, EPO, WIPO, JPO, SIPO), focusing heavily on patent chemistry claims, synthetic examples, and pharmacology. |
| Property & Spectral Data | Provides experimental and predicted physical properties, spectra (NMR, MS, IR), and commercial availability integrated directly into substance detail cards. | Granular, queryable property fields covering experimental melting points, boiling points, solubility, bioactivity (target affinities, IC50), and spectroscopic data. |
| Interdisciplinary Coverage | Broad cross-disciplinary reach bridging chemistry with medicine (MEDLINE integration), biotechnology, nanotechnology, agriculture, and materials engineering. | Specialized focus on synthetic organic chemistry, medicinal chemistry, organometallics, and pharmacology, with direct integration to Reaxys Medicinal Chemistry. |
| Licensing & Institutional Access | Available primarily via institutional enterprise site licenses or designated concurrent-user seat subscriptions negotiated directly with CAS / ACS. | Available through institutional enterprise subscriptions from Elsevier, often integrated with ScienceDirect and Scopus enterprise agreements. |
| When to Choose Which | Choose SciFinder when you need exhaustive literature coverage, prior-art patent landscapes, CAS Registry verification, or broad interdisciplinary science discovery. | Choose Reaxys when optimizing bench synthesis, comparing reaction conditions and yields, extracting exact experimental procedures, or researching historical pre-1960 chemistry. |
| Sources & Verification | Verified via Chemical Abstracts Service (CAS) official documentation, SciFinder Discovery Platform resources, and ACS standards (https://www.cas.org, read 2026-11-07). | Verified via Elsevier Reaxys official specifications, product manuals, and database documentation (https://www.elsevier.com/solutions/reaxys, read 2026-11-07). |
Common questions
Common questions about CAS SciFinder vs Elsevier Reaxys
Can I use Reaxys and SciFinder interchangeably?
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While both platforms cover extensive chemical literature and reaction data, their core architectures differ. SciFinder is a broader literature and patent discovery engine centered on the CAS Registry, whereas Reaxys is a structured data extraction engine optimized for bench-level reaction conditions and experimental properties.
Which platform has better reaction search capabilities?
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Synthetic organic chemists often favor Reaxys for daily bench reaction planning because it displays side-by-side yields, solvents, catalysts, and exact experimental procedures directly in search results. However, SciFinder offers broader coverage of patent reactions and complex interdisciplinary transformations.
Why do many chemistry departments license both SciFinder and Reaxys?
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Academic and corporate research institutions frequently license both databases because they complement each other. Researchers use SciFinder to ensure no prior art or patent literature is missed and use Reaxys to rapidly troubleshoot and optimize reaction steps in the laboratory.
Does Reaxys use CAS Registry Numbers?
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Reaxys includes CAS Registry Numbers where available as searchable cross-reference data, but it uses its own internal substance identifiers and substance structure models based on Beilstein and Gmelin registries.
Going deeper
