About
Open-Meteo is an open-source weather API platform designed to give developers, researchers, and hobbyists frictionless access to accurate, high-resolution weather data — completely free for non-commercial use with no API key required. It partners with trusted national weather services to aggregate and serve both global (11 km) and mesoscale (1 km) weather model data, intelligently selecting the best-fit model for any given location on Earth. The Forecast API delivers current conditions and hourly forecasts up to 16 days ahead, covering variables such as temperature, wind speed, relative humidity, and more. Local weather models are refreshed every hour, incorporating real-time feeds from airplanes, buoys, radar systems, and satellites for maximum freshness and accuracy. The Historical Weather API exposes over 80 years of hourly data at 10 km resolution — a 50 TB dataset — making it invaluable for climate research, machine learning model training, and trend analysis. Recent data from 1 km resolution models is also continuously archived, bridging current forecasts with near-past records. All responses are returned in a clean, easy-to-parse JSON format, making integration straightforward for any technology stack. Open-Meteo is ideal for application developers building weather-aware features, data scientists training predictive models, researchers exploring historical climate patterns, and businesses needing reliable meteorological data without commercial API costs.
Key Features
- No API Key Required: Free access for non-commercial use with zero authentication setup — just call the endpoint and receive data instantly.
- High-Resolution Forecast Models: Leverages both global (11 km) and mesoscale (1 km) weather models from national weather services, automatically selecting the best model per location.
- 80+ Years of Historical Weather Data: Access over eight decades of hourly weather records at 10 km resolution, backed by a 50 TB dataset ideal for ML training and climate research.
- Hourly Model Updates: Local weather models refresh every hour using live data from airplanes, buoys, radar systems, and satellites for near-real-time accuracy.
- Simple JSON API: All weather data is returned in a clean, developer-friendly JSON format with intuitive query parameters for latitude, longitude, and variable selection.
Use Cases
- Building weather-aware mobile or web applications without incurring API costs during development and non-commercial deployment.
- Training machine learning and AI models on historical climate data using 80+ years of high-resolution hourly weather records.
- Academic and climate research requiring long-term, reliable meteorological datasets at no cost.
- Integrating real-time weather conditions into IoT systems, smart home devices, or agriculture monitoring platforms.
- Powering dashboards and data visualizations that display current forecasts or historical weather trends for any global location.
Pros
- Completely Free for Non-Commercial Use: No API key, no sign-up friction, and no usage caps for personal and open-source projects — reducing time-to-integration dramatically.
- Extensive Historical Archive: 80+ years of hourly data is rare among free weather APIs and makes Open-Meteo uniquely valuable for data science and climate research workflows.
- Open-Source and Transparent: The codebase is publicly available, enabling self-hosting, community contributions, and full auditability of the forecasting pipeline.
- Global High-Resolution Coverage: Combines multiple national weather service models to ensure precise, location-aware forecasts anywhere in the world.
Cons
- Commercial Use Requires a Paid Plan: Free access is restricted to non-commercial purposes; businesses and commercial applications must subscribe to a paid tier.
- No Native SDKs or Client Libraries: Open-Meteo provides a raw REST/JSON API without official SDKs, so developers must handle HTTP requests and response parsing themselves.
- Limited Non-Weather Data: The platform focuses exclusively on meteorological data; it does not provide ancillary features like geocoding, maps, or weather alerts out of the box.
Frequently Asked Questions
Do I need an API key to use Open-Meteo?
No. For non-commercial use, Open-Meteo requires no API key or account registration. Simply call the API endpoint with your desired coordinates and parameters.
How far ahead can Open-Meteo forecast?
Open-Meteo provides hourly forecasts up to 16 days ahead. The first few days use high-resolution local models (1 km), while subsequent days rely on global models (11 km).
How much historical data is available?
The Historical Weather API covers over 80 years of hourly data at 10 km resolution. Recent weeks are also available at 1 km resolution via archived local model runs.
Can I use Open-Meteo for commercial projects?
Commercial use requires a paid subscription. The free tier is licensed for non-commercial purposes only. Pricing plans are available on the Open-Meteo website.
Can Open-Meteo be self-hosted?
Yes. Open-Meteo is fully open-source and can be self-hosted on your own infrastructure, giving you full control over data access, latency, and compliance requirements.
