Decision Support · Side-by-side
Compare pricing, strengths, and use cases so it is easier to pick the right fit.
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For most solo practitioners and small firms, Fastcase offers better value with its bar association integrations and visual search mapping, despite a clunkier mobile app. OneLaw wins on citation accuracy and enterprise security, but its higher price and slower indexing make it a better fit for larger firms that need airtight precedent verification. The single biggest difference is Fastcase's cost-effectiveness versus OneLaw's superior citation depth.
Fastcase
OneLaw
Scores at a glance
Choose Fastcase if
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Key differences
Facts side by side
| Fastcase | OneLaw | |
|---|---|---|
| Free plan | ||
| Mobile app | ||
| API access |
Common questions
Yes, for most solos Fastcase is the better choice because it's cheaper (often free through bar associations) and easier to start using. OneLaw's higher price and lack of mobile app make it overkill unless you need enterprise security.
Fastcase has a mobile app, but users report it's laggy and less polished than the web version. OneLaw does not have a mobile app at all, so you'll need a laptop or desktop.
OneLaw has superior citation accuracy and verification. Fastcase's 'Authority Check' is decent but not as deep as Westlaw or OneLaw, so if you need bulletproof citations, go with OneLaw.
Both are designed for legal professionals. Fastcase is often accessed through bar association portals, so you typically need to be a member. OneLaw requires firm verification. They're not for general consumers.
Fastcase has a gentler learning curve because you can use natural language and visual maps. OneLaw requires more precise prompting, which takes practice. Fastcase wins on onboarding ease.
Yes, both tools let you upload PDFs and DOCX files. Fastcase's Vincent AI can summarize briefs, and OneLaw can index firm knowledge bases. Both work, but OneLaw can be slow with large zip files.
Fastcase wins for everyday legal research on a budget; OneLaw wins for airtight citations at a premium price.
If you're a solo or small-firm lawyer, start with Fastcase — it's affordable, easy to access through your bar association, and the visual mapping is genuinely helpful. For larger firms where citation accuracy and security are non-negotiable, OneLaw is worth the investment, but be ready for a steeper learning curve and higher cost.
