Free ISS Tracker Comparison
Geometry apps predict when the station is sunlit. Weather still decides if you see it.
ISS Pass Predictor · Is the ISS Visible Tonight?
Options
| Tool | Best at | Tradeoff | |------|---------|----------| | NASA Spot the Station | Free app with push alerts, trusted (its email and text alerts ended in June 2025) | Less interactive exploration | | Heavens-Above | Deep pass tables, no account needed | Denser UI | | iss.guru | Fast next-pass lookup | Fewer visibility flags in-browser | | Orbital Radar ISS tracker | Visual tracker + passes | App/site focus, not a Learn path | | AstroPhotosGY ISS Pass Predictor | Free browser, visibility flags, lat/lon links, Learn path, and ISS pass emails from Alerts | Alerts by email, not phone push |
Practical combo
Many observers keep Spot the Station app alerts (or email alerts from Alerts), then open a browser table the afternoon of a pass. Add Tonight Score so you do not wait under a solid deck of cloud for a faint pass.