Custom Subdomains

Create memorable, consistent URLs for your tunnels with custom subdomains. Perfect for demos, development, and sharing.

🎯 Basic Custom Subdomains

Simple Custom Subdomain

# Create tunnel with custom subdomain
$ instatunnel 3000 --subdomain myapp
✅ Tunnel created: https://myapp.instatunnel.my
📋 URL copied to clipboard!
# Short form
$ instatunnel 3000 -s myapp

Instead of random URLs like abc123.instatunnel.my, get memorable URLs like myapp.instatunnel.my

Random Subdomains

# Let InstaTunnel generate a random subdomain
$ instatunnel 3000
✅ Tunnel created: https://k8m9n2.instatunnel.my
# Every tunnel gets a unique 6-character subdomain
$ instatunnel 8000
✅ Tunnel created: https://x3p7q1.instatunnel.my

When no subdomain is specified, InstaTunnel automatically generates a unique 6-character subdomain.

Subdomain Best Practices

# Environment-based patterns
$ instatunnel 3000 --subdomain myapp-dev
✅ Tunnel created: https://myapp-dev.instatunnel.my
# Feature branch patterns
$ instatunnel 3000 --subdomain myapp-feature-auth
✅ Tunnel created: https://myapp-feature-auth.instatunnel.my
# Personal development patterns
$ instatunnel 3000 --subdomain john-myapp
✅ Tunnel created: https://john-myapp.instatunnel.my

Use consistent naming patterns for organized development workflows.

⚠️ Subdomain Availability

Handling Conflicts

# When subdomain is already taken
$ instatunnel 3000 --subdomain myapp
❌ Error: subdomain already taken
# Try with a suffix or variation
$ instatunnel 3000 --subdomain myapp-dev
✅ Tunnel created: https://myapp-dev.instatunnel.my
# Or use a random subdomain
$ instatunnel 3000
✅ Tunnel created: https://m7k3x9.instatunnel.my

Subdomains are first-come-first-served. Try variations or use random subdomains if your preferred name is taken.

Subdomain Rules

Must be 3-63 characters long
Can contain letters (a-z), numbers (0-9), and hyphens (-)
Must start and end with a letter or number
Cannot contain uppercase letters or special characters
Cannot start or end with a hyphen

💡 Subdomain Tips

Free vs Pro Features

Free Plan
  • • Custom subdomains (*.instatunnel.my)
  • • No reservation - first-come-first-served
  • • 24-hour session duration
  • • 3 simultaneous tunnels
Pro Plan
  • • Custom subdomains (*.instatunnel.my)
  • • Custom domains (yourapp.com)
  • • Unlimited session duration
  • • 10 simultaneous tunnels

🎯 Best Practice: Use descriptive subdomains for demos and consistent subdomains for development environments. For quick testing, random subdomains work perfectly.

Need a quick path?

Plan o mite, hitsuyo na toki ni guided start o tsukatte kudasai.

For MCP endpoints on Pro/Business, use instatunnel 8787 --mcp.

Docs | InstaTunnel