Auth0 Migration Guide
Migrate users and authentication flows from existing auth providers to Auth0.
Overview
When to Use This Skill
- Migrating from another auth provider to Auth0
- Bulk importing existing users
- Gradually transitioning active user bases
- Updating JWT validation in APIs
When NOT to Use
- Starting fresh with Auth0 - Use for new projects without existing users
- Already using Auth0 - This is for migrating TO Auth0, not between Auth0 tenants
- Only adding MFA or features - Use feature-specific skills if just adding capabilities
Migration Approaches
- Bulk Migration: One-time user import (recommended for small/inactive bases)
- Gradual Migration: Lazy migration over time (recommended for large active bases)
- Hybrid: Import inactive users, lazy-migrate active users
Step 0: Detect Existing Auth Provider
Check if the project already has authentication:
Search for common auth-related patterns in the codebase:
| Pattern | Indicates |
|---|
signInWithEmailAndPassword
, | Firebase Auth |
| , , | Existing auth hooks |
| , | Passport.js |
| , , | OAuth/OIDC |
| , , | Token-based auth |
| , , | Auth routes |
If existing auth detected, ask:
I detected existing authentication in your project. Are you:
- Migrating to Auth0 (replace existing auth)
- Adding Auth0 alongside (keep both temporarily)
- Starting fresh (remove old auth, new Auth0 setup)
Migration Workflow
Step 1: Export Existing Users
Export users from your current provider. See User Import Guide for detailed instructions:
- Exporting from Firebase
- Exporting from AWS Cognito
- Exporting from Supabase
- Exporting from Custom Database
Required data per user:
- Email address
- Email verified status
- Password hash (if available)
- User metadata/profile data
- Creation timestamp
Step 2: Import Users to Auth0
Import users via Dashboard, CLI, or Management API.
Quick start:
bash
# Via Auth0 CLI
auth0 api post "jobs/users-imports" \
--data "connection_id=con_ABC123" \
--data "users=@users.json"
For detailed instructions:
- User JSON Format
- Password Hash Algorithms
- Import Methods
- Monitoring Import Progress
- Common Import Errors
Step 3: Migrate Application Code
Update your application code to use Auth0 SDKs.
See Code Migration Patterns for detailed before/after examples:
Frontend:
- React Migration
- Next.js Migration
- Vue.js Migration
- Angular Migration
- React Native Migration
Backend:
- Express.js Migration
- API JWT Validation
Provider-Specific:
- Firebase to Auth0
- Supabase to Auth0
- Clerk to Auth0
After migrating code, use framework-specific skills:
- for React applications
- for Next.js applications
- for Vue.js applications
- for Angular applications
- for Express.js applications
- for React Native/Expo applications
Step 4: Update API JWT Validation
If your API validates JWTs, update to validate Auth0 tokens.
Key differences:
- Algorithm: HS256 (symmetric) → RS256 (asymmetric)
- Issuer: Custom →
https://YOUR_TENANT.auth0.com/
- JWKS URL:
https://YOUR_TENANT.auth0.com/.well-known/jwks.json
See JWT Validation Examples for:
- Node.js / Express implementation
- Python / Flask implementation
- Key differences and migration checklist
Gradual Migration Strategy
For production applications with active users, use a phased approach:
Phase 1: Parallel Auth
Support both Auth0 and legacy provider simultaneously:
typescript
// Support both providers during migration
const getUser = async () => {
// Try Auth0 first
const auth0User = await getAuth0User();
if (auth0User) return auth0User;
// Fall back to legacy provider
return await getLegacyUser();
};
Phase 2: New Users on Auth0
- All new signups go to Auth0
- Existing users continue on legacy provider
- Migrate users on next login (lazy migration)
Phase 3: Forced Migration
- Prompt remaining users to "update account"
- Send password reset emails via Auth0
- Set deadline for legacy system shutdown
Phase 4: Cleanup
- Remove legacy auth code
- Archive user export for compliance
- Update documentation
Common Migration Issues
| Issue | Solution |
|---|
| Password hashes incompatible | Use Auth0 custom DB connection with lazy migration |
| Social logins don't link | Configure same social connection, users auto-link by email |
| Custom claims missing | Add claims via Auth0 Actions |
| Token format different | Update API to validate RS256 JWTs with Auth0 issuer |
| Session persistence | Auth0 uses rotating refresh tokens; update token storage |
| Users must re-login | Expected for redirect-based auth; communicate to users |
Reference Documentation
User Import
Complete guide to exporting and importing users:
- Exporting from Common Providers
- User JSON Format
- Password Hash Algorithms
- Import Methods
- Monitoring & Troubleshooting
Code Migration
Before/after examples for all major frameworks:
- React Patterns
- Next.js Patterns
- Express Patterns
- Vue.js Patterns
- Angular Patterns
- React Native Patterns
- API JWT Validation
Related Skills
Core Integration
- - Initial Auth0 setup after migration
SDK Skills
- - React SPA integration
- - Next.js integration
- - Vue.js integration
- - Angular integration
- - Express.js integration
- - React Native/Expo integration
References