How to expose localhost:4242 to the internet
You have something listening on port 4242 and need a link you can paste into Slack, a webhook dashboard, or your phone. This is the copy-paste path.
Stripe's official samples often use 4242. Handy when you want a port that is obviously for webhooks. The tunnel does not care what framework you run. It forwards HTTPS to whatever is bound on 4242.
Quick start
curl -fsSL https://get.ngsrv.com | bash
ngsrv token <YOUR_TOKEN>
ngsrv http 4242
You get a public URL like https://furry-otter-1842.tnl.ngsrv.com that routes to http://localhost:4242.
What usually runs on 4242
- Stripe webhook sample apps
- custom webhook handlers
Typical dev command: node server.js
Install the CLI
# macOS (Homebrew)
brew install ngsrv/tap/ngsrv
# macOS / Linux
curl -fsSL https://get.ngsrv.com | bash
# Windows (PowerShell)
irm https://get.ngsrv.com/windows | iex
Sign up at ngsrv.com/register if you need a token. Free tier, no card.
Run the tunnel
With your server already up on port 4242:
ngsrv http 4242
Sample output:
forwarding https://furry-otter-1842.tnl.ngsrv.com -> http://localhost:4242
status online
Stable subdomain (optional)
Random names change when you restart. For webhooks or client previews, reserve one:
ngsrv http 4242 --subdomain hooks
# -> https://hooks.tnl.ngsrv.com
When it breaks
connection refused — Nothing is listening on 4242. Confirm with lsof -i :4242 (macOS/Linux) or netstat -ano | findstr :4242 (Windows).
401 invalid token — Re-run ngsrv token <YOUR_TOKEN> from the dashboard.
Tunnel drops — ngsrv reconnects on its own. Persistent drops usually mean VPN or proxy interference.