How to set up a captive portal for guest WiFi

A captive portal is the page a device sees before it is allowed on the network: the "sign in to use this WiFi" screen. Hotels and cafés use it to show terms, collect a name, or sell access.

How the flow works

A guest joins the network. Their first request is intercepted and answered with a login page instead of the internet. Once they authenticate — or pay — they are granted access for a set time, and their browser is told it is online.

The detail most setups get wrong

Every operating system checks whether it is online by fetching its own probe URL — Google, Apple, Microsoft and Samsung all use different ones. If the portal answers those probes incorrectly, the login sheet never opens, or never closes. A captive portal has to handle each probe distinctly.

For a portal that works out of the box, including time-limited and paid access, Spekii Edge Shield bundles it into the router plugin rather than requiring a separate appliance.