Compare
Clerk vs FusionAuth
FusionAuth is self-hosted and open source, while Clerk is a managed SaaS with built-in UI components.
Which to pick
Pick Clerk if you want…
- Turnkey auth and user management
- SaaS user management
- Integrations with Next.js, React or Expo (on Clerk's list, not FusionAuth's)
Pick FusionAuth if you want…
- Self-hosted CIAM with predictable pricing
- Self-hosted auth platform
- Integrations with OAuth 2.0, OpenID Connect or SAML v2 (on FusionAuth's list, not Clerk's)
Clerk is a SaaS-only user management platform, while FusionAuth can be self-hosted with unlimited users.
Side by side
- What it is
- Clerk:Clerk provides embeddable UI components, APIs, and dashboards for full-stack user authentication, management, and billing.
- FusionAuth:FusionAuth is a self-hostable CIAM platform offering authentication, MFA, SSO and fine-grained authorization via APIs.
- Best for
- Clerk:Turnkey auth and user management
- FusionAuth:Self-hosted CIAM with predictable pricing
- Who it’s for
- Clerk:Developers building web or mobile apps that need authentication, multi-tenant user management, and subscription billing.
- FusionAuth:Developers and teams building apps that need customizable, scalable identity management.
- Pricing
- Clerk:Freemium
- FusionAuth:Freemium
- Plans
- Clerk:Hobby $0 · Pro $20 per month, billed annually · Business $250 per month, billed annually
- FusionAuth:Community Free · Starter $162 per month (billed annually) · Essentials $240 per month (billed annually)
- Works with
- Clerk:Next.js, React, Expo, React Router, Astro, Supabase, Convex, Vercel
- FusionAuth:OAuth 2.0, OpenID Connect, SAML v2, LDAP, SCIM, Kafka, Docker, Kubernetes
Clerk features
- Pre-built UI components. Drop-in React components for sign-up, sign-in, profile, organization and billing UI.
- Multi-tenancy & org management. Components and APIs to create organizations, switch accounts, invite members and manage roles.
- MFA & advanced security. Built-in multifactor authentication, bot detection, passkeys and SOC 2/CCPA compliance.
- Session & device management. Full session lifecycle with active device monitoring and revocation.
- Billing & subscriptions. Ready-to-use subscription billing UI, plan definition and revenue tracking.
- SDKs for modern frameworks. Libraries for Next.js, React, Expo, React Router, Astro and more.
- API keys & machine auth. Generate secure API keys and M2M tokens for user-scoped access.
- CLI for AI agents. Command-line tool to configure Clerk without leaving the terminal.
FusionAuth features
- API-first identity. All authentication, authorization and user management functions are exposed via full-featured APIs.
- Multi-factor authentication. Supports basic TOTP as well as advanced MFA methods like email, SMS, voice and intelligent policies.
- Enterprise-grade isolation. Dedicated deployments with controlled upgrades and HA hosting for critical workloads.
- Customizable theming. Advanced application theming and internationalized UI for branded login experiences.
- Passkeys & WebAuthn. Passwordless authentication using WebAuthn cross-platform authenticators.
- Flexible deployment. Run on-prem, self-hosted, hybrid, air-gapped or in FusionAuth Cloud.
Clerk vs FusionAuth FAQ
Is Clerk or FusionAuth free?+
Clerk has a free plan (Hobby) and paid plans. FusionAuth has a free plan (Community); paid plans start at $162/month (Starter).
Do Clerk and FusionAuth integrate with the same tools?+
Their integration lists don't overlap: Clerk lists Next.js, React, Expo, React Router and 4 more; FusionAuth lists OAuth 2.0, OpenID Connect, SAML v2, LDAP and 4 more.
On DevHunt
Based on each tool's website and DevHunt data. Details may change; check the official sites.