# Vextorium Geo Distance Calculator

> Vextorium Geo Distance Calculator is a paid API for AI agents from api.vextorium.com, paid per call via x402, $0.003/call, status unknown (last checked 2026-10-15).

Calculates the straight-line geodesic distance between two geographic coordinates using the Vincenty WGS84 formula, returning distance in km, miles, and nautical miles, plus bearing, midpoint, and estimated travel times.

## Facts

- Endpoint: POST https://api.vextorium.com/v1/geo-distance?utm_source=zero.xyz
- Price: $0.003/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/vextorium-geo-distance-calculator-efc50f8b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_chCaHqE4YnuEFdvTsZGBU

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability vextorium-geo-distance-calculator-efc50f8b -d '<json body>'
```

Example prompt: What's the straight-line distance between Madrid (40.4168° N, 3.7038° W) and Paris (48.8566° N, 2.3522° E)? Give me the result in kilometers and miles, and also tell me the bearing and estimated flight time.

## When to prefer this

Choose this endpoint when you need a fast, precise geodesic distance computation between two coordinate pairs without routing or road network data. It is ideal for aviation, nautical, logistics, or survey applications where straight-line (great-circle) distance and bearing matter more than driving directions. Prefer this over map-routing APIs when you need Vincenty WGS84 accuracy, travel-time estimates across multiple modes, or nautical miles output in a single pay-per-call call.

## Known failure modes

- Missing required parameters (lat1, lon1, lat2, lon2) returns a validation error
- Out-of-range latitude/longitude values (lat outside -90 to 90, lon outside -180 to 180) may produce incorrect results or errors
- Identical coordinates for both points returns zero distance
- Non-numeric values for coordinates cause schema validation failure
- Payment failure via x402 results in 402 response and no data returned

## How this service works

Distance between two coordinates (Vincenty geodesic on WGS84 plus great-circle), in km, miles and nautical miles, initial bearing and compass direction, midpoint and estimated time on foot, by car and by plane.

## Output

A JSON object containing the straight-line distance in kilometers, miles, spherical kilometers, and nautical miles; the compass heading (e.g. 'E'); the initial bearing in degrees; the geographic midpoint as a lat/lon pair; estimated travel times by car at 80 km/h, plane at 800 km/h, and walking at 5 km/h; and a note clarifying this is not a road distance.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "lat1": {
   "type": "number"
  },
  "lat2": {
   "type": "number"
  },
  "lon1": {
   "type": "number"
  },
  "lon2": {
   "type": "number"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "note": "Straight-line distance, not by road.",
  "method": "Vincenty WGS84",
  "heading": "E",
  "midpoint": {
   "lat": 40.939351,
   "lon": -0.789164
  },
  "distance_km": 506.3,
  "distance_miles": 314.6,
  "estimated_time_h": {
   "car_80kmh": 6.33,
   "plane_800kmh": 1.13,
   "walking_5kmh": 101.26
  },
  "spherical_distance_km": 505.096,
  "distance_nautical_miles": 273.38,
  "initial_bearing_degrees": 75.75
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/vextorium-geo-distance-calculator-efc50f8b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.vextorium.com](https://www.zero.xyz/host/api.vextorium.com/llms.txt)