Casdoor vs. Auth0
Auth0, now part of Okta, is a managed identity service. Casdoor is an open-source identity server that you can run yourself or use as a hosted service. The protocols overlap almost completely; the choice is mostly about who operates the system, where the data lives, and how cost grows with your user base.
Summary
| Casdoor | Auth0 | |
|---|---|---|
| Source | Open source, Apache-2.0 | Proprietary |
| Deployment | Self-hosted anywhere, or hosted | Auth0's cloud; private cloud on enterprise plans |
| Pricing basis | Free to self-host; hosted and enterprise plans are flat-rate | Monthly active users, with features gated by plan |
| Data location | Your own database, in any region or on-premises | Auth0-managed regions |
| OAuth 2.0, OIDC, SAML | Yes | Yes |
| CAS, LDAP server, RADIUS server | Built in | Not offered |
| Login customization | Edited per application in the admin console, including custom HTML and CSS | Universal Login templates and Actions |
| Custom logic | REST API and webhooks | Actions (hosted JavaScript) |
| AI agents and MCP | Built-in MCP server; OAuth 2.1 authorization server for MCP | Separate add-on products |
Cost
Auth0 bills by monthly active users. That is cheap for a prototype and can grow quickly: a consumer product with many occasional users pays for every one of them, and features such as enterprise connections, MFA options, or organizations depend on the plan.
Casdoor has no per-user charge when you self-host. You pay for a server and a database. If you would rather not run it, the hosted plans are priced per instance, not per user.
Control and data residency
With Auth0, user data lives in Auth0's infrastructure in the region you select.
With Casdoor, users are rows in a database you own: MySQL, PostgreSQL, SQL Server, Oracle, SQLite, and others are supported. That makes it straightforward to keep identities in a specific country, inside a private network, or in an air-gapped deployment, and to query or back up the data with your normal tools.
Features Auth0 does not have
- Legacy protocols. Casdoor is a CAS server, an LDAP server, and a RADIUS server, so older applications, VPNs, and Wi-Fi controllers can use the same directory.
- Regional sign-in providers. WeChat, DingTalk, Lark, Alipay, QQ, and many others are among the 70+ built-in OAuth providers.
- Payments. Products, payments, and subscriptions are part of Casdoor, which is convenient for SaaS products that sell plans to the same users they authenticate.
- Casbin authorization. Permissions use Casbin models (ACL, RBAC, ABAC) that you can also enforce in your own services.
Where Auth0 is stronger
- You do not operate anything. Upgrades, scaling, and availability are Auth0's job, backed by an SLA.
- Attack protection. Bot detection, breached-password detection, and adaptive MFA are mature managed features. Casdoor provides captcha providers, IP allowlists, and MFA, and you assemble the rest yourself.
- Ecosystem. Auth0 has a large marketplace, extensive quickstarts, and many third-party tutorials.
- Compliance paperwork. If your customers require a vendor with specific certifications, a large managed provider already has them.
AI agents and MCP
Casdoor includes an MCP server for its own management API and is an OAuth 2.1 authorization server for MCP servers you build: Dynamic Client Registration, PKCE, consent, resource indicators, and JWKS-based token validation work out of the box and are not priced separately.
Moving from Auth0 to Casdoor
- Export users from Auth0 and import them into Casdoor through the user import in the admin console or the REST API.
- During the transition, add Auth0 to Casdoor as an OAuth provider so users whose passwords have not been migrated can still sign in through Auth0.
- Point each application at Casdoor's OIDC discovery URL. Applications that use a standard OIDC library usually need only the issuer, client ID, and client secret changed. See Standard OIDC client.
When to choose which
Choose Auth0 if you want a fully managed service with an SLA and are comfortable with usage-based pricing.
Choose Casdoor if you want open source, predictable cost as you grow, control over where identity data is stored, legacy protocol support, or built-in MCP authorization.
See also the comparison overview.