Random tunnel URLs work fine for quick testing, but when you need to share a stable, branded URL with clients or team members, custom domains make all the difference. Available on Pro plans and above.

Why Custom Domains?

Instead of sharing https://r4nd0m.tunels.io, you can use your own domain like https://dev.mycompany.com. Benefits include:

  • Professional appearance when sharing with clients or stakeholders
  • Stable URLs that don't change between tunnel sessions
  • Whitelisting — add your domain to webhook allow-lists once
  • Team workflows — everyone knows where to find the dev server

Step 1: Add a CNAME Record

In your DNS provider (Cloudflare, Route53, GoDaddy, etc.), add a CNAME record:

Type: CNAME
Name: dev
Value: tunnels.tunels.io
TTL: 300

This tells DNS to route dev.mycompany.com traffic to Tunels infrastructure.

Step 2: Register the Domain in Tunels

Use the CLI or dashboard to register your custom domain:

tunels domain add dev.mycompany.com

Tunels will verify the CNAME record and provision a TLS certificate automatically via Let's Encrypt.

Step 3: Start Your Tunnel

tunels http 3000 --hostname dev.mycompany.com

Your local server is now accessible at https://dev.mycompany.com with a valid TLS certificate.

Wildcard Domains

On Gold and Premium plans, you can configure wildcard domains. Set up a wildcard CNAME (*.dev.mycompany.com) and each team member can use their own subdomain:

tunels http 3000 --hostname alice.dev.mycompany.com
tunels http 3000 --hostname bob.dev.mycompany.com

TLS Certificates

Tunels handles TLS certificate provisioning and renewal automatically. Certificates are issued within seconds of your first connection and renewed before expiry. You never need to manage certificates manually.

Conclusion

Custom domains transform Tunels from a development tool into a professional integration point. Set it up once, and your team and clients always know where to find your latest work.