Documentation / Anonymous Mode & Duration

Anonymous Mode & Duration

Use stunl without an account, or set auto-shutdown timers on any tunnel

Anonymous Mode

Pass -anonymous to create a tunnel with no API key and no account. Useful for quick one-off shares when you don't need the full feature set.

Quick start 
$ stunl -port 3000 -anonymous

  ● STUNL (anonymous)

  ╭── ◎ ── HTTP
  │   HTTPS    https://anon-7f3k2.stunl.io
  │   Local    localhost:3000
  │   Expires  30 minutes

Anonymous Limits

Limit Value
Session duration 30 minutes
Bandwidth 100 MB
Protocol HTTP only
Tunnels per day per IP 3
Visitor warning Interstitial page shown before reaching your site

Blocked in anonymous mode

x TCP / UDP tunnels
x Custom domains
x Custom IDs
x Password protection
x Multi-port tunnels
x OAuth authentication
x Reserved ports
x End-to-end encryption

Anonymous vs Free Tier

Creating a free account at portal.stunl.com removes most anonymous restrictions without requiring a credit card.

Anonymous Free Tier
Session duration 30 min 60 min
Bandwidth 100 MB 2 GB
Protocols HTTP HTTP + WebSocket
Visitor warning Yes No
API key required No Yes

Duration Flag

The -duration flag sets an auto-shutdown timer on any tunnel (not just anonymous). When the duration expires, the tunnel shuts down gracefully with a 30-second cleanup period.

Quick start 
$ stunl -port 8080 -duration 2h

  ● STUNL

  ╭── ◎ ── HTTP
  │   HTTPS    https://abc123.stunl.io
  │   Local    localhost:8080
  │   Expires  2 hours
Flag Description
-anonymous Run without an API key (anonymous limits apply)
-duration Auto-shutdown after duration (e.g., 30m, 2h, 24h)

How It Works

Anonymous mode skips API key authentication entirely. The server assigns a random subdomain and enforces strict limits. A warning interstitial is shown to visitors before they reach your site, informing them the tunnel is anonymous.

Duration starts a countdown timer when the tunnel connects. At expiry, the CLI sends a graceful shutdown signal and waits up to 30 seconds for in-flight requests to complete before closing the connection.

Examples

Quick anonymous share for a demo 
$ stunl -port 3000 -anonymous
Authenticated tunnel that auto-closes after 2 hours 
$ stunl -port 8080 -duration 2h -id staging-preview
CI webhook receiver that shuts down after 30 minutes 
$ stunl -port 9000 -duration 30m
24-hour tunnel for an overnight test run 
$ stunl -port 4000 -duration 24h -id overnight-test

Next Steps