FAQ
Quick answers to common questions.
Is PreviewBox free?
Yes — PreviewBox is free for developers. There are no plans to charge for basic tunneling.
How is this different from ngrok or localtunnel?
PreviewBox is built around a full-screen terminal app: tunnels, logs and status are all visible in one place while you work. It also adds a web dashboard with analytics, traffic recording and replay, uptime monitoring, smart alerts, webhooks and team support.
Can I tunnel non-HTTP services?
Yes. Use `prevbox serve tcp <port>` for any TCP-based service — game servers, SSH, databases, or custom protocols. See the TCP tunnels guide.
Can I tunnel a Minecraft server?
Absolutely. Run your server, then `prevbox serve tcp 25565` and share the host and port with your friends. No port forwarding needed.
Can I choose my subdomain?
Yes — pass `--subdomain my-app` to `prevbox serve`. Otherwise you get a random subdomain like happy-fox-42.
Do I get HTTPS automatically?
Yes. Every tunnel gets a valid TLS certificate, so your URL is always https:// — required by webhooks, browsers and mobile apps.
How do I stop a tunnel?
In the TUI, press `s` on the Serve page to stop all tunnels, or `q` to quit the app (which also stops tunnels). You can also delete tunnels from the dashboard.
Can I run multiple tunnels at once?
Yes — as many as you need, mixing HTTP and TCP on different ports and subdomains.
Do I need Node.js?
The CLI requires Node.js 18 or later. Your local dev server can be anything — Node, Python, Ruby, Java, whatever.
Where does the CLI store my data?
Everything lives in ~/.previewbox — config.json for server settings and a token file for your session, both created with restricted permissions.
How secure is my tunnel?
Traffic is encrypted end-to-end (HTTPS/TLS). The dashboard adds two-factor authentication, API keys, session management and an audit log. Webhook deliveries are HMAC-signed.
Can I use PreviewBox for webhook testing?
That’s one of the best use cases — give Stripe, GitHub or Twilio your tunnel URL and deliveries hit your local machine instantly.
Still stuck? Start with Getting Started, check the CLI reference, or run prevbox and press h for in-terminal help.