HTTP Error 503 Service Unavailable: what it means and how to get your site back

A 503 means the server is up but refuses to serve pages right now. It is overloaded, in maintenance mode, or the program behind the site has stopped. Your files are almost always fine.

What to do, in order

1. Wait two minutes and reload. A traffic spike or a host restart often clears on its own.
2. WordPress stuck in maintenance: an update was cut off. Delete the file named .maintenance in the site's main folder, using your host's file manager or FTP.
3. Shared hosting: log in to the control panel and look for "resource usage" or "CPU limit". If you hit the limit, a plugin or a bot is eating it. Ask the host which process.
4. Plugin or theme fault: rename the wp-content/plugins folder to plugins-off. If the site returns, rename it back and switch plugins on one by one.
5. Your own server (nginx or Apache in front of PHP, Node or Python): the program behind it died. Run sudo systemctl status php*-fpm or check your app service, then restart it and read its log.
6. Cloudflare shows the 503: look at the page footer. If it names your host, the fault is on your server, not Cloudflare.

If it keeps coming back, send me the address and I will tell you which layer is answering with the 503.

Want the rest of your site checked after it is back? Run a free 40-point check at tinkeraudit.com.