# OpenWeatherMap API

**Provider:** OpenWeatherMap
**Category:** weather
**Base URL:** `https://api.openweathermap.org/data/3.0`
**Auth:** api-key — `?appid=your_api_key`
**Rate Limit:** 60 calls/min (free)
**Free Tier:** Yes — [object Object]
**Pricing:** Free tier available (freemium)
**Docs:** https://openweathermap.org/api

## Description

OpenWeatherMap provides weather data from 40,000+ stations and weather models covering 200,000 cities. Access current conditions, 5-day/3-hour forecasts, hourly 4-day forecasts, 16-day daily forecasts, historical data going back 40 years, and weather alert polygons.

## Endpoints

| Method | Endpoint | Description |
|--------|----------|-------------|
| GET | `https://api.openweathermap.org/data/3.0/onecall` | One-call API: current, minutely, hourly, daily, alerts |
| GET | `https://api.openweathermap.org/data/3.0/onecall/timemachine` | Historical weather for a specific date |
| GET | `https://api.openweathermap.org/data/3.0/onecall/day_summary` | Daily weather aggregates for any date |
| GET | `https://api.openweathermap.org/data/3.0/air_pollution` | Current air quality index and pollutants |
| GET | `https://api.openweathermap.org/data/3.0/air_pollution/forecast` | Forecasted air pollution data |

## Authentication

Include your API key as the appid query parameter.

```
?appid=your_api_key
```

## Sample Request

```bash
curl "https://api.openweathermap.org/data/3.0/onecall?lat=51.5074&lon=-0.1278&units=metric&exclude=minutely&appid=$OWM_API_KEY"
```

## Sample Response

```json
{
  "lat": 51.5074,
  "lon": -0.1278,
  "timezone": "Europe/London",
  "current": {
    "temp": 12.5,
    "feels_like": 10.2,
    "humidity": 78,
    "wind_speed": 5.4,
    "weather": [{"main": "Clouds", "description": "overcast clouds"}]
  },
  "daily": [{"dt": 1680825600, "temp": {"day": 14, "night": 9}, "summary": "Overcast clouds"}]
}
```

## Pricing Details

Free: 1k calls/day. Startup: $40/mo (100k/day). Developer: $180/mo (300k/day). Professional: $470/mo (unlimited). Historical data extra.

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*Source: [API Map](https://apimap.dev/apis/openweathermap/) — CC BY 4.0*