Built for the numbers the dashboard leaves out.
Most route planners assume an EV charges at its advertised peak, drives at its EPA rating, and fills at a steady rate like a fuel tank. Many cars don't: conservative battery management, no preconditioning, a pack that's a few years old. ChargeCliff models what those tools leave out.
Who this is for
Anyone planning a trip in one of 42 vehicles: the cautious Lexus RZ and Toyota bZ4X, Tesla's steadier curve, the Nissan Leaf's steep taper, plus trucks, luxury sedans and most of what sits between. It is most useful for cars whose published charging speed and real charging speed are far apart.
Under the surface it is a small physics engine with every formula derived on the how it works page. Four profiles are calibrated against a named, published dyno or road-test benchmark. The rest are estimates from public charging reports, and are labelled that way in both the API and the interface.
If a number here is wrong for a car you drive, the most useful thing you can send is a logged session: start and end percentage, minutes, charger rating, temperature. It goes into the profile with its source and a pinned test. Send it on LinkedIn, or open an issue on the repo.
What "calibrated" means here
Each charge curve was tuned by running the session simulation against a published number: a factory dyno figure, a winter road test, a magazine's steady-speed range test. Breakpoints are adjusted until the model lands inside the published range. Those checks live in the automated test suite, so a later change that moves a result outside its published range fails the build.
A profile without a named benchmark is marked
verified: false in the API and noted in the interface.
It is an estimate from a shared platform, and is presented as one.
What is being calculated
The thermal charging curve & optimal unplug point
A DC fast-charge session integrated across 1% state-of-charge steps rather than a single kWh-over-kW division, because the curve isn't flat. Includes the cold-weather intake limit below 68°F and reports the state of charge where waiting longer stops being worth it.
The highway reality check
Aerodynamic drag scales with the square of speed; a 70 to 75 mph cruise plus cabin heat in cold weather can cut EPA-rated range 35 to 50%. Reports the full-charge figure and the 80% to 10% window most drivers plan a trip around.
Battery aging & the used-EV auditor
A State-of-Health estimate from age and odometer alone (no OBD-II dongle, no manufacturer app) and the compounding power derate an aged pack's BMS applies on top of its own factory curve.
Per-minute billing
Per-minute billing charges the same rate however fast power is flowing. A slow-tapering EV can pay more per kWh, and sometimes more per mile than gasoline, on the same plan as a fast-charging 800V car.