localhost:8000
You probably meant to go to localhost:8000, and ended up here by accident.
In computer networking, localhost is a hostname that refers back to the same computer. The number following the colon is a port number. The port 8000 is a long-standing default in the Python web ecosystem: it's what Django uses for runserver, what Python's built-in python -m http.server binds to, and the default for FastAPI examples served via Uvicorn.
It also shows up as the default for several modern AI / LLM serving tools, including vLLM's OpenAI-compatible server and LangServe, so a lot of AI coding tutorials send people to localhost:8000 too.
Our best guess is that just like us, you ended up here while working on web development with one of these (or another framework), and your browser auto-completed your request, sending you to localhost8000.com instead :)
# stop the autocomplete
Once your browser has learned localhost8000.com, it will keep suggesting it. To remove the bad entry:
- Chrome, Edge, Brave (any Chromium): start typing
localhostin the address bar, use the arrow keys to highlight thelocalhost8000.comsuggestion, then press Shift + Delete (on Mac: Shift + Fn + Delete). - Firefox: same idea - highlight the suggestion with the arrow keys, then press Shift + Delete.
- Safari: Safari has no per-suggestion shortcut. Go to Safari → Settings → Privacy → Manage Website Data, search for
localhost8000, and remove it. You may also want to clear it from history (History → Clear History, scoped to the last hour).
# common localhost ports
Different stacks default to different ports. If you're not sure what port your local server is actually on, this is roughly what you'll see in the wild:
| Port | Commonly used by |
|---|---|
| 3000 | Node.js, Express, Create React App, Next.js (dev) |
| 4200 | Angular CLI (ng serve) |
| 5000 | Flask (default), ASP.NET Core; also AirPlay on macOS |
| 5173 | Vite (default) |
| 5432 | PostgreSQL |
| 6379 | Redis |
| 8000 | Django, Python http.server, FastAPI / Uvicorn examples |
| 8080 | Tomcat, Jenkins, http-server, common alt-HTTP |
| 8888 | Jupyter Notebook |
| 9000 | PHP-FPM, SonarQube, MinIO |
# localhost:8000 not responding?
If you reached this page because your local server isn't actually running, here are the usual suspects:
- The dev server isn't started. Sounds obvious, but it's the most common cause - check the terminal tab you thought it was running in.
- Something else is bound to port 8000. Check with
lsof -i :8000(macOS / Linux) ornetstat -ano | findstr :8000(Windows). Kill the stray process, or run your server on a different port. - The server is listening on the wrong interface. If it's bound to
0.0.0.0it's reachable; if it's only on a specific IP,localhostmay not resolve to it. Re-bind to127.0.0.1or0.0.0.0. - HTTPS vs HTTP mismatch. Most local dev servers serve plain HTTP. If your browser is rewriting to
https://localhost:8000, forcehttp://explicitly. - A firewall or VPN is blocking loopback traffic. Rare, but corporate VPN clients sometimes do this. Toggle the VPN off as a quick test.