# Geo Calc Bounding Box from Radius

> Geo Calc Bounding Box from Radius is a paid API for AI agents from geo-calc.x402tookit.com, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-29).

Computes the minimum bounding box (min/max lat/lon) enclosing a circular radius in meters around a geographic point, with correct handling of poles and the antimeridian.

## Facts

- Endpoint: GET https://geo-calc.x402tookit.com/bbox-radius?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-29
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/geo-calc-bounding-box-from-radius-dd581da6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_Lir8davv14b76QuT1Xqa3

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 geo-calc-bounding-box-from-radius-dd581da6
```

Example prompt: What's the bounding box (min and max latitude and longitude) that encloses a 25,000-meter radius around the point at latitude 51.5074, longitude -0.1278?

## When to prefer this

Choose this endpoint when you need a fast, edge-case-correct bounding box for a circular radius around a geographic point — especially when the area might span the antimeridian or encompass a pole. It is ideal for pre-filtering spatial database queries, setting map viewports, or defining geofences, and handles the tricky 180° and polar wraparound cases that naive degree-arithmetic approaches get wrong.

## Known failure modes

- Missing required query parameters (lat, lon, radiusM) returns an error
- radiusM outside the 1 to 5,000,000 meter range returns a validation error
- Invalid numeric values for lat or lon return a parse error
- Extremely large radii near poles may return degraded results with warnings in the reasons array

## How this service works

Bounding box (min/max latitude and longitude) enclosing a radius in meters around a point, with pole and 180 degree handling.

## Output

Returns a JSON object containing minLat, maxLat, minLon, maxLon defining the bounding box, the radius used, flags indicating whether the bounding box includes a pole (includesPole), crosses the antimeridian (crossesAntimeridian), or spans all longitudes (spansAllLongitudes), the latitude half-height in meters, the ellipsoid model used, a summary, and any disclaimer or degraded-mode notes.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "lat",
      "lon",
      "radiusM"
     ],
     "properties": {
      "lat": {
       "type": "number",
       "description": "Center latitude"
      },
      "lon": {
       "type": "number",
       "description": "Center longitude"
      },
      "radiusM": {
       "type": "number",
       "description": "Radius in meters, 1 to 5,000,000"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "asOf": {
       "type": [
        "null",
        "string"
       ]
      },
      "maxLat": {
       "type": [
        "null",
        "number"
       ]
      },
      "maxLon": {
       "type": [
        "null",
        "number"
       ]
      },
      "minLat": {
       "type": [
        "null",
        "number"
       ]
      },
      "minLon": {
       "type": [
        "null",
        "number"
       ]
      },
      "source": {
       "type": [
        "null",
        "string"
       ]
      },
      "radiusM": {
       "type": [
        "null",
        "number"
       ]
      },
      "reasons": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "summary": {
       "type": [
        "null",
        "string"
       ]
      },
      "verdict": {
       "type": [
        "null",
        "string"
       ]
      },
      "degraded": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "ellipsoid": {
       "type": [
        "null",
        "string"
       ]
      },
      "disclaimer": {
       "type": [
        "null",
        "string"
       ]
      },
      "notChecked": {
       "type": [
        "array",
        "null"
       ],
       "items": {
        "type": "string"
       }
      },
      "includesPole": {
       "type": [
        "boolean",
        "null"
       ]
      },
      "spansAllLongitudes": {
       "t
… (truncated)
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/geo-calc-bounding-box-from-radius-dd581da6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from geo-calc.x402tookit.com](https://www.zero.xyz/host/geo-calc.x402tookit.com/llms.txt)