Custom Subdomains

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

Sign in with an InstaTunnel account to choose a subdomain, including on the Free plan. Anonymous tunnels use random names only. First-party and security-sensitive names such as api, login, and support cannot be claimed.

🎯 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

Available names are first-come-first-served for signed-in users. Reserved names are unavailable even when not in use. Try a different name or use a random subdomain.

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.

Where should I start in InstaTunnel docs?

Evidence and trust

Release cadence

Security controls

Reliability runbooks

Documentation