# boring-api · geo — Polygon Area Calculator

> boring-api · geo — Polygon Area Calculator is a paid API for AI agents from geo.boring-api.com, paid per call via x402, $0.0005/call, status unknown (last checked 2026-09-15).

Computes the area of a GeoJSON polygon using pure in-Worker spatial math, with no external API calls.

## Facts

- Endpoint: POST https://geo.boring-api.com/polygon-area
- Price: $0.0005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/boring-api-geo-polygon-area-calculator-ae6ed4bd
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_o_u9_ZRsZwp5rGBlFJGxV

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 boring-api-geo-polygon-area-calculator-ae6ed4bd -d '<json body>'
```

Example prompt: What's the area of this polygon? Here's the GeoJSON: {"type":"Polygon","coordinates":[[[-73.9857,40.7484],[-73.9857,40.7580],[-73.9720,40.7580],[-73.9720,40.7484],[-73.9857,40.7484]]]}

## When to prefer this

Choose this endpoint when you need fast, cheap, serverless polygon area computation from a GeoJSON geometry with no external API dependency. Ideal for GIS workflows, land measurement, geofencing analysis, or any scenario requiring area calculation without a full mapping platform subscription.

## Known failure modes

- Invalid or malformed GeoJSON polygon input returns an error
- Missing polygon property in request body
- Unclosed polygon ring (first and last coordinate not matching) may cause errors
- Self-intersecting polygon may produce incorrect results
- Non-polygon GeoJSON types (Point, LineString) may be rejected

## How this service works

Pure-library spatial math and timezone lookup. Distance, bearing, polygons, point-in-polygon, timezone-by-coords. No external API calls — all computed in-Worker.

## Output

Returns an object containing the computed area of the provided GeoJSON polygon, calculated entirely in-Worker without external API dependencies.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "polygon": {
   "type": "object",
   "description": "GeoJSON Polygon Feature/Geometry"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/boring-api-geo-polygon-area-calculator-ae6ed4bd/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from geo.boring-api.com](https://www.zero.xyz/host/geo.boring-api.com/llms.txt)