Best Free Weather APIs in 2026
Compare 6 free weather APIs: Open-Meteo, OpenWeatherMap, WeatherAPI, Visual Crossing, Tomorrow.io, and Weatherbit. Code examples and rate limits.
Why Use a Weather API?
Weather data powers everything from travel apps and farming tools to logistics optimization and smart home automation. Whether you're building a simple weather widget or a complex agricultural forecasting system, there's a free API that fits your needs.
The key differences between weather APIs come down to: data freshness (how often they update), historical depth (how far back you can query), geographic resolution (how precise the location data is), and free tier generosity (how many requests you get).
Quick Comparison
| API | Free Tier | Auth | Rate Score | Docs |
|---|---|---|---|---|
| Open-Meteo | 10,000 calls/day | None | 10/10 | Docs |
| OpenWeatherMap | 1,000 calls/day | API Key | 7/10 | Docs |
| WeatherAPI | 1M calls/month | API Key | 10/10 | Docs |
| Visual Crossing | 1,000 records/day | API Key | 8/10 | Docs |
| Tomorrow.io | 500 calls/day | API Key | 7/10 | Docs |
| Weatherbit | 50 calls/day | API Key | 5/10 | Docs |
Detailed Reviews
1. Open-Meteo
Open-Meteo is the gold standard for free weather APIs. No API key required, no sign-up needed, and 10,000 requests per day. It's open-source, fast, and covers global weather data with hourly resolution.
What sets Open-Meteo apart is its simplicity. You can get weather data with a single URL — no headers, no authentication, no SDK. It also offers historical weather data going back to 1940, making it perfect for data science projects.
Key Strengths:
- No API key or sign-up required
- 10,000 free requests/day
- Historical data back to 1940
- Open-source and self-hostable
- 16-day forecasts with hourly resolution
View Code Example
// No API key needed!
const lat = 40.7128, lon = -74.0060; // New York
const res = await fetch(
`https://api.open-meteo.com/v1/forecast?latitude=${lat}&longitude=${lon}¤t=temperature_2m,weathercode,windspeed_10m,humidity_2m&daily=temperature_2m_max,temperature_2m_min&timezone=auto`
);
const data = await res.json();
console.log(`Temperature: ${data.current.temperature_2m}°C`);
console.log(`Wind: ${data.current.windspeed_10m} km/h`);
console.log(`Tomorrow: ${data.daily.temperature_2m_max[1]}°C high`);2. OpenWeatherMap
The most popular weather API among developers, with 2+ million users. OpenWeatherMap has been around since 2012 and has the largest community, most tutorials, and best third-party integrations.
Key Strengths:
- Largest developer community
- Built-in weather icons and condition descriptions
- Air quality and UV index data
- Bulk historical data available
View Code Example
const city = "London";
const res = await fetch(
`https://api.openweathermap.org/data/2.5/weather?q=${city}&appid=YOUR_KEY&units=metric`
);
const data = await res.json();
console.log(`${data.name}: ${data.main.temp}°C`);
console.log(`Feels like: ${data.main.feels_like}°C`);
console.log(`${data.weather[0].description}`);3. WeatherAPI
WeatherAPI offers an incredibly generous free tier — 1 million API calls per month. It covers current weather, forecasts, astronomy data (sunrise/sunset, moon phase), and even sports weather.
Key Strengths:
- 1 million free calls/month (most generous paid-style free tier)
- Astronomy data (moon phases, sunrise/sunset)
- IP-based auto-location
- 14-day forecast on free tier
View Code Example
const res = await fetch(
"https://api.weatherapi.com/v1/forecast.json?key=YOUR_KEY&q=Tokyo&days=3"
);
const data = await res.json();
console.log(`${data.location.name}: ${data.current.temp_c}°C`);
console.log(`Sunrise: ${data.forecast.forecastday[0].astro.sunrise}`);
console.log(`Moon: ${data.forecast.forecastday[0].astro.moon_phase}`);4. Visual Crossing
Visual Crossing is the best choice for historical weather data and analytics. Their API returns clean, well-structured data that's perfect for data science, machine learning, and business intelligence projects.
Key Strengths:
- Best historical weather data
- Clean CSV and JSON output
- 50+ years of historical data
- Weather alerts included
View Code Example
const city = "Paris";
const res = await fetch(
`https://weather.visualcrossing.com/VisualCrossingWebServices/rest/services/timeline/${city}/last7days?unitGroup=metric&key=YOUR_KEY`
);
const data = await res.json();
data.days.forEach(day => {
console.log(`${day.datetime}: ${day.temp}°C (${day.conditions})`);
});5. Tomorrow.io
Tomorrow.io (formerly Climacell) provides hyper-local weather data with minute-by-minute precipitation forecasts. Their proprietary data sources go beyond traditional weather stations.
Key Strengths:
- Minute-by-minute precipitation nowcasting
- Proprietary micro-weather data
- Road conditions and construction weather
- Pollen and air quality data
View Code Example
const res = await fetch(
"https://api.tomorrow.io/v4/weather/realtime?location=42.3478,-71.0466&apikey=YOUR_KEY"
);
const data = await res.json();
const v = data.data.values;
console.log(`Temp: ${v.temperature}°C`);
console.log(`Humidity: ${v.humidity}%`);
console.log(`UV Index: ${v.uvIndex}`);6. Weatherbit
Weatherbit provides current weather, 16-day forecasts, and air quality data. Their free tier is limited but the data quality is solid, especially for air quality monitoring.
Key Strengths:
- Good air quality data (AQI)
- Severe weather alerts
- Energy-specific weather data
- 16-day forecast on free tier
View Code Example
const res = await fetch(
"https://api.weatherbit.io/v2.0/current?city=Sydney&country=AU&key=YOUR_KEY"
);
const data = await res.json();
const w = data.data[0];
console.log(`${w.city_name}: ${w.temp}°C`);
console.log(`AQI: ${w.aqi}`);
console.log(`${w.weather.description}`);Which Weather API Should You Choose?
For hobby projects and learning: Open-Meteo — zero friction, no key needed, generous limits.
For production apps: WeatherAPI — 1M free calls/month gives you room to grow before needing to pay.
For data science and ML: Visual Crossing — clean data formats and deep historical archive.
For hyper-local weather: Tomorrow.io — minute-by-minute precipitation and micro-weather data.
Browse All 6+ APIs
This is part of our comprehensive Best Free APIs in 2026 directory with 6+ APIs across 11 categories.
Frequently Asked Questions
Open-Meteo is the only major weather API that requires no API key, no sign-up, and no credit card. You get 10,000 free requests per day with high-quality global weather data.
WeatherAPI offers 1 million free API calls per month, making it the most generous among weather APIs that require an API key. Open-Meteo offers 10,000/day (300K/month) with no key required.
Yes. Open-Meteo provides free historical weather data going back to 1940. Visual Crossing also offers historical data on their free tier, though with daily request limits.
OpenWeatherMap and WeatherAPI both work well for mobile apps. OpenWeatherMap has the most tutorials and community resources, while WeatherAPI's IP-based auto-location is convenient for mobile.
Yes, several free weather APIs include severe weather alerts: OpenWeatherMap, Visual Crossing, and Weatherbit all provide alert data on their free tiers.