---
url: >-
  https://adk.nht.io/api/@nhtio/adk/batteries/tools/geo_basics/variables/geoDistanceTool.md
description: Great-circle (haversine) distance between two geographic coordinates.
---

# Variable: geoDistanceTool

```ts
const geoDistanceTool: Tool<SpooledArtifact>;
```

Defined in: [batteries/tools/geo\_basics/index.ts:43](https://github.com/NHTIO/ADK/blob/v1.20260605.0/src/batteries/tools/geo_basics/index.ts#L43)

Great-circle (haversine) distance between two geographic coordinates.

## Remarks

Uses the Earth's mean radius (6371.0088 km). Returns both kilometres and miles.