# Beaufort Wind Scale API
> The Beaufort wind scale as an API, computed locally and deterministically. The classify endpoint turns a measured wind speed — in metres per second, kilometres per hour, knots, miles per hour or feet per second — into its Beaufort force (0 calm to 12 hurricane), with the descriptive name (light breeze, gale, storm …), the corresponding sea state and the mean open-sea wave height, plus the speed expressed in every unit. The force endpoint looks up a Beaufort number and returns its wind-speed range in all units, its description, sea condition and wave height. The convert endpoint converts a wind speed across metres per second, kilometres per hour, knots, miles per hour and feet per second and reports the matching Beaufort force (1 knot = 0.514444 m/s). Speeds use the standard 10-metre reference height and wave heights are open-sea means. Everything is computed locally and deterministically, so it is instant and private. Ideal for sailing, marine, aviation, drone, weather and outdoor app developers, wind-warning and sea-state tools, and meteorology education. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 3 endpoints. This is the Beaufort wind scale; for the feels-like wind chill use a feels-like API and for live wind observations a weather data API.

## Authentication
All requests require your oanor API key in the `x-oanor-key` header. Get one at https://www.oanor.com/developer/keys.

```bash
curl -H "x-oanor-key: oanor_live_…" "https://api.oanor.com/beaufort-api/..."
```

## Pricing
- **Free** (Free) — 4,500 calls/Mo, 2 req/s
- **Starter** ($4/Mo) — 48,000 calls/Mo, 6 req/s
- **Pro** ($12/Mo) — 230,000 calls/Mo, 15 req/s
- **Mega** ($39/Mo) — 1,350,000 calls/Mo, 40 req/s

## Endpoints

### Beaufort

#### `GET /v1/classify` — Classify wind speed

**Parameters:**
- `speed` (query, required, string) — Wind speed Example: `10`
- `unit` (query, optional, string) — ms, kmh, knots, mph, fts Example: `ms`

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/beaufort-api/v1/classify?speed=10&unit=ms"
```

**Response:**
```json
{
    "data": {
        "note": "Beaufort force from the WMO scale (10 m reference height). Wave height is the mean for the open sea and assumes a long fetch.",
        "inputs": {
            "unit": "ms",
            "speed": 10
        },
        "speed_ms": 10,
        "description": "Fresh breeze",
        "sea_condition": "Moderate waves, many whitecaps",
        "beaufort_force": 5,
        "speed_all_units": {
            "ms": 10,
            "fts": 32.8084,
            "kmh": 36,
            "mph": 22.3694,
            "knots": 19.4384
        },
        "mean_wave_height_m": 2
    },
    "meta": {
        "timestamp": "2026-06-05T11:30:35.137Z",
        "request_id": "5070ef02-e0b6-48b8-90a8-3b00e850a01b"
    },
    "status": "ok",
    "message": "Classify wind speed",
    "success": true
}
```

#### `GET /v1/convert` — Wind speed convert

**Parameters:**
- `speed` (query, required, string) — Wind speed Example: `40`
- `unit` (query, optional, string) — ms, kmh, knots, mph, fts Example: `knots`

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/beaufort-api/v1/convert?speed=40&unit=knots"
```

**Response:**
```json
{
    "data": {
        "note": "Wind speed converted across m/s, km/h, knots, mph and ft/s, with the matching Beaufort force. 1 knot = 0.514444 m/s.",
        "inputs": {
            "unit": "knots",
            "speed": 40
        },
        "converted": {
            "ms": 20.5778,
            "fts": 67.5124,
            "kmh": 74.08,
            "mph": 46.0312,
            "knots": 40
        },
        "description": "Gale",
        "beaufort_force": 8
    },
    "meta": {
        "timestamp": "2026-06-05T11:30:35.233Z",
        "request_id": "f096480f-43eb-4dda-ba1f-94c3308dbef2"
    },
    "status": "ok",
    "message": "Wind speed convert",
    "success": true
}
```

#### `GET /v1/force` — Beaufort force lookup

**Parameters:**
- `force` (query, required, string) — Beaufort force (0–12) Example: `8`

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/beaufort-api/v1/force?force=8"
```

**Response:**
```json
{
    "data": {
        "note": "Speed ranges are at the standard 10 m reference height.",
        "inputs": {
            "force": 8
        },
        "description": "Gale",
        "sea_condition": "Moderately high waves, edges of crests break into spindrift",
        "speed_range_ms": {
            "max": 20.7,
            "min": 17.2
        },
        "speed_range_kmh": {
            "max": 74.52,
            "min": 61.92
        },
        "speed_range_mph": {
            "max": 46.3,
            "min": 38.48
        },
        "speed_range_knots": {
            "max": 40.24,
            "min": 33.43
        },
        "mean_wave_height_m": 5.5
    },
    "meta": {
        "timestamp": "2026-06-05T11:30:35.340Z",
        "request_id": "051910e8-4076-4aec-8d33-a4ddc3ab965a"
    },
    "status": "ok",
    "message": "Beaufort force lookup",
    "success": true
}
```

### Meta

#### `GET /v1/meta` — Spec

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/beaufort-api/v1/meta"
```

**Response:**
```json
{
    "data": {
        "notes": "Speeds at the 10 m reference height. unit: ms (default), kmh, knots, mph or fts. Wave heights are open-sea means.",
        "service": "beaufort-api",
        "endpoints": {
            "GET /v1/meta": "This document.",
            "GET /v1/force": "Speed range (m/s, km/h, knots, mph), description and wave height for a Beaufort force 0–12.",
            "GET /v1/convert": "Convert a wind speed across m/s, km/h, knots, mph and ft/s, with the Beaufort force.",
            "GET /v1/classify": "Beaufort force, description and wave height from a wind speed."
        },
        "description": "Beaufort wind-scale calculator: classify a wind speed into a Beaufort force with sea state and wave height, look up the speed range of a force, and convert wind-speed units."
    },
    "meta": {
        "timestamp": "2026-06-05T11:30:35.445Z",
        "request_id": "11ec31bb-11f5-4ebd-b9c9-420958c4badf"
    },
    "status": "ok",
    "message": "Meta",
    "success": true
}
```


---
Marketplace page: https://www.oanor.com/api/beaufort-api
OpenAPI spec: https://www.oanor.com/api/beaufort-api/openapi.json