Data and route methodology

How is an on-demand road route calculated?

After submitted places are resolved, the planner sends the ordered points, travel mode and supported preferences to a configured routing service. A successful response may contain road distance, estimated duration, route geometry, elevation information and manoeuvres.

Avoid-toll, avoid-highway and avoid-ferry controls are requests to the routing service, not guarantees. The displayed provider and retrieval time describe the calculation that was actually returned.

City-to-city road and air distance

The distance calculator resolves towns and cities against the local place index, then requests a driving route directly between the selected reference coordinates. Its primary result is the returned road distance and estimated duration for one available route.

The same coordinates also feed a Haversine calculation using a mean Earth radius of 6,371.0088 kilometres. That air-line value is a geographic comparison, not a road route. If the road calculation is unavailable, a separately labelled rough planning estimate applies a documented detour and average-speed assumption rather than pretending that the air-line distance follows roads.

Fuel and EV estimates

Liquid-fuel mode uses distance and either litres per 100 kilometres or US miles per US gallon. Electric mode uses kWh per 100 kilometres or 100 miles and can include an explicit charging-loss percentage.

Round-trip and contingency choices are applied visibly. Consumption, price and currency are visitor inputs. The calculator does not obtain live prices, exchange rates, tolls or parking charges.

Unit conversions

Conversions use published constants. US and imperial gallons remain separate, and reciprocal fuel-economy conversions are not treated like linear distance or volume conversions. Results are rounded only for display.

Maps and place suggestions

Town and city suggestions are served from the local index where possible. A full address can be suggested through Geoapify when configured. The route diagram is generated from returned geometry and remains available without map tiles.

When a route has usable geometry, the interactive road map loads tiles through this site using the configured map service. The map shows OpenStreetMap data attribution. If tiles fail, the route diagram and directions remain available.

Caching and comparison

A successful route may be held briefly to avoid repeating the same provider request. The retrieval label continues to describe when the underlying result was obtained. A visitor can deliberately request a second calculation; differences do not by themselves prove that either route is wrong.

Limitations of the result

A route reflects the data and options available at retrieval time. Provider coverage, map updates, vehicle restrictions, traffic and conditions vary; the result is not a live road-control instruction. See the Disclaimer for safe-use limits and Corrections for reporting a specific error.