What are the IP ranges and ports used by Office Online?¶
Office Online does not provide IP ranges for partners to use to restrict traffic (i.e. IP-based ACLs). Office Online adds new servers and datacenters regularly and such IP lists will be out of date often. Hosts should use proof keys if they wish to verify that requests are coming from Office Online.
All WOPI communication is done using port 443, the standard HTTPS port.