JWT vs Session Guide
🎫 JWT
- Stateless — no server storage
- Self-contained (user data in token)
- Works across microservices
- Mobile-friendly (no cookies needed)
- Cannot be invalidated before expiry
- Larger payload than session ID
- Token must be stored client-side
🍪 Session
- Stateful — session stored on server
- Easy to invalidate (logout)
- Small cookie (just session ID)
- HttpOnly cookie prevents XSS theft
- Requires shared storage (Redis/DB)
- Harder to scale horizontally
- Built-in browser cookie support
| Feature | JWT | Session |
|---|---|---|
| Instant logout | ❌ Hard | ✅ Easy |
| Microservices | ✅ Native | ⚠️ Needs shared store |
| Mobile apps | ✅ Great | ⚠️ Works |
| XSS resistance | ⚠️ Use httpOnly cookie | ✅ HttpOnly |
| CSRF resistance | ✅ (in header) | ⚠️ Need CSRF token |
| DB lookup per request | ✅ No | ❌ Yes |
Recommendation
Use JWT when: Building APIs for mobile/SPA, microservices, cross-domain auth, or when statelessness is critical.
Use Sessions when: Building traditional web apps, need reliable instant logout, simpler mental model is preferred.
Use JWT when: Building APIs for mobile/SPA, microservices, cross-domain auth, or when statelessness is critical.
Use Sessions when: Building traditional web apps, need reliable instant logout, simpler mental model is preferred.