Every charging session delivers a specific amount of energy — but what does that mean in terms of distance? If you charged for 40 kWh, did you gain 150 km of range or 250 km? The answer depends on your vehicle's efficiency, and until today, the booking card at /bookings gave you no way to know.

That gap is now closed. Every booking card now shows one of two pieces of information, whichever is most relevant: the estimated range charged in kilometers, or the session duration for completed bookings.

When the vehicle has specification data available — specifically, its power rating — we compute the estimated range by multiplying energy delivered by output power and an efficiency factor. The result is displayed as a compact green badge: "187.5 km estimated range". This gives you an immediate, intuitive sense of how far that charging session will take you.

The computation accounts for real-world charging factors and losses that prevent 100% of energy from reaching the wheels. This provides a realistic approximation.

For vehicles where output power data is not available, the booking card falls back to showing the charging session duration instead. This is formatted as a human-readable string: "1h 23m" or "45m 12s". The duration appears in a cyan badge, visually distinct from the green range badge, so you can instantly tell which metric is being displayed.

The two states are mutually exclusive and clearly differentiated. A booking card either shows estimated range or charging duration. There is no ambiguity and no empty state — every booking card now has one or the other.

Under the hood, the backend services now include range and duration metrics in booking detail responses, persisting values at booking time so historical estimates remain stable.

For historical bookings created before this feature was deployed, a fallback estimate is calculated from current specifications. If even that fallback isn't available, the frontend shows the charging duration instead.

This is a small visual change with meaningful situational awareness. When you review your charging history, seeing "187.5 km estimated range" on a card tells you something actionable — that session was enough for your daily commute. And for sessions without range data, the duration at least tells you how long you were plugged in.