This usually happens when Mixpanel can’t map the request’s IP to a city, or when the IP isn’t included in the request. In those cases, City/Region can be “undefined” while Country is still populated. This is expected for some traffic (e.g., VPNs, limited IP databases, or server-side sends without client IP) (Supported data types: Falsy values).
Ways to improve City coverage:
- Ensure the client IP is sent: for server-side or proxy setups, pass the end-user IP in the event as ip (events) or $ip (profiles), so geolocation is derived from the user rather than your server (Define IP Address; Default properties).
- Manually set geolocation: include $city, $region, and mp_country_code (events) or $country_code (profiles) directly in payloads; these override IP-derived values (Manual geolocation tracking).
- Use latitude/longitude for higher precision: set $latitude and $longitude so Mixpanel reverse-geocodes to a city (Manual geolocation tracking).
- If you don’t want geolocation at all, disable it: configure SDKs to not use IP, or set ip=0 per event/profile (Disabling geolocation; Define IP Address — Ignore IP).
Note: Auto Page View is client-side; if some events still lack city, it’s likely due to IPs that can’t be mapped in MaxMind, VPNs, or intermittent absence of IP. Mixpanel uses IP to derive $city/$region/mp_country_code at ingestion and discards the IP afterward (Geolocation overview).
