Host Your Own JWT Authentication System with n8n

Overview

A production-ready authentication workflow implementing secure user registration, login, token verification, and refresh token mechanisms using n8n. This provides a complete authentication backend without external auth services.

Platform: n8n workflows + Data Tables
Security: JWT with HMAC-SHA256, SHA-512 password hashing, unique salts

Key Features

Authentication Components

  • User Registration: Secure password hashing (SHA-512 + unique salts)
  • Login System: Generates access tokens (15 min) and refresh tokens (7 days) using JWT
  • Token Verification: Validates access tokens for protected endpoints
  • Token Refresh: Issues new access tokens without requiring re-login

Security Implementation

  • HMAC-SHA256 JWT signatures
  • Hashed refresh tokens in database
  • Protection against rainbow table attacks
  • No plain text password storage
  • Generic error messages to prevent information leakage
  • Database token revocation for logout-all-devices

Why This Approach

✅ No external services: Everything runs in n8n - no Auth0, Firebase, or third-party dependencies
✅ Production-ready security: Industry-standard JWT implementation with proper token lifecycle
✅ Easy integration: Simple REST API endpoints that work with any frontend framework
✅ Fully customizable: Adjust token lifespans, add custom user fields, implement business logic
✅ Well-documented: 30+ sticky notes explain every security decision

Setup Requirements

Prerequisites

  • n8n instance (cloud or self-hosted)
  • n8n Data Tables feature enabled

Data Tables Structure

users table:

  • id
  • email
  • username
  • password_hash
  • refresh_token

refresh_tokens table:

  • id
  • user_id
  • token_hash
  • expires_at

Generate Secret Keys

node -e "console.log(require('crypto').randomBytes(32).toString('hex'))"

Generate two different secrets:

  • ACCESS_SECRET
  • REFRESH_SECRET

Configuration Steps

  1. Update “SET ACCESS AND REFRESH SECRET” nodes with generated keys
  2. Or migrate to n8n Variables for better security
  3. Connect Data Table nodes to created tables
  4. Save and activate workflow
  5. Note webhook URLs

API Endpoints

Register User

Endpoint: POST /webhook/register-user

{
  "email": "user@example.com",
  "username": "username",
  "password": "password123"
}

Login

Endpoint: POST /webhook/login

{
  "email": "user@example.com",
  "password": "password123"
}

Returns:

{
  "accessToken": "...",
  "refreshToken": "...",
  "user": {...}
}

Verify Token

Endpoint: POST /webhook/verify-token

{
  "access_token": "your_access_token"
}

Refresh Token

Endpoint: POST /webhook/refresh

{
  "refresh_token": "your_refresh_token"
}

Frontend Integration

Login Flow (Vue.js/React)

const response = await fetch('https://your-n8n.app/webhook/login', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({ email, password })
});
const { accessToken, refreshToken } = await response.json();
localStorage.setItem('accessToken', accessToken);

Authenticated Requests

const data = await fetch('https://your-api.com/protected', {
  headers: { 'Authorization': `Bearer ${accessToken}` }
});

Use Cases

  • SaaS applications needing user authentication
  • Mobile app backends
  • Internal tools requiring access control
  • MVP/prototype authentication without third-party costs
  • Learning JWT and auth system architecture

Customization Options

Component Customization
Token Lifespan Modify expiration times in “Create JWT Payload” nodes
User Fields Add custom fields to registration and user profile
Password Rules Update validation in “Validate Registration Request” node
Token Rotation Implement refresh token rotation for enhanced security

Security Best Practices

⚠️ Important Production Requirements:

  • Change default secret keys before production use
  • Use HTTPS for all webhook endpoints
  • Store secrets in n8n Variables (not hardcoded)
  • Regularly rotate secret keys in production
  • Consider rate limiting for login endpoints

Key Takeaways

  1. Self-hosted authentication eliminates dependency on external auth providers
  2. Two-token system balances security (short-lived access) with UX (long-lived refresh)
  3. n8n Data Tables provide persistent storage without additional database setup
  4. Industry-standard security with JWT, proper hashing, and token lifecycle management
  5. Production-ready with comprehensive documentation and security considerations

Implementation Architecture

User Registration → Password Hashing (SHA-512 + Salt) → Store in Data Table
User Login → Verify Password → Generate JWT Tokens → Return to Client
Protected Request → Verify Access Token → Grant/Deny Access
Token Expired → Use Refresh Token → Issue New Access Token
  • n8n workflow template: Link
  • JWT specification
  • n8n Data Tables documentation
  • OWASP authentication guidelines

Tag Analysis

Content Type: article - Web article capture
Topics: automation, development, tools - Core subject areas
Status: inbox - New capture requiring review
Metadata: technical, tutorial, actionable - Deep-dive technical tutorial with implementation steps

Bases Filtering Suggestions

TABLE tags, status, type
WHERE type = "article" 
  AND contains(tags, "automation")
  AND contains(tags, "technical")
SORT created DESC

Power Queries:

  • tags contains "automation" AND tags contains "development" - Find automation + dev articles
  • tags contains "tutorial" AND tags contains "actionable" - Implementation guides
  • tags contains "technical" AND status = "inbox" - New technical content to review
  • type = article AND tags contains "tools" - Tool-related articles

Total Tags: 8 (1 content type + 3 topics + 1 status + 3 metadata)