TL;DR
Open-Meteo provides a free, open-source weather API that requires no API key or registration for non-commercial projects. It serves high-resolution hourly forecasts, hourly-updated local models, and an 80-year historical dataset, with code on GitHub and data shared under CC BY 4.0.
What happened
Open-Meteo is publishing a freely accessible weather API intended for non-commercial use. The service automatically selects suitable weather models for the requested coordinates and offers hourly forecast data at resolutions between roughly 1 km and 11 km. Localized models are refreshed every hour and are used for the first days of a forecast, while global models extend coverage out to about 16 days. The platform also exposes a historical weather API with more than 80 years of hourly records at a 10 km resolution; the provider says this archive totals tens of terabytes. The software behind the API is open-source on GitHub under the AGPLv3 licence, and the underlying data are licensed under CC BY 4.0. Individuals and developers can query the API without registration or an API key; the operator recommends a paid subscription for commercial uses or if daily requests are expected to exceed about 10,000 calls.
Why it matters
- Lower barrier to entry: developers and hobbyists can fetch weather data without registration or keys for non-commercial projects.
- Open data + permissive data licence (CC BY 4.0) enables reuse and adaptation of weather data, including commercial reuse of the data itself.
- Availability of long-term hourly records supports training and analysis for research or machine learning projects.
- Hourly-updated local models and fine spatial resolution can improve short-term planning and time-sensitive applications.
Key facts
- No API key, registration, or credit card required for non-commercial access.
- Forecast spatial resolution ranges from about 1 km (mesoscale) to 11 km (global), provided hourly.
- Local weather models are updated every hour; global models supply forecasts up to around 16 days.
- Historical Weather API offers over 80 years of hourly data at 10 km resolution and the archive is roughly 50 TB in size (as stated).
- Codebase is published on GitHub under the AGPLv3 licence.
- Weather data are licensed under Attribution 4.0 International (CC BY 4.0).
- Recommended to consider a paid API subscription for commercial use or when expecting more than ~10,000 API calls per day.
- The provider aggregates real-time inputs such as aircraft, buoys, radar and satellite observations to inform numerical weather predictions.
- Multiple specialised APIs are listed (forecast, historical, marine, air quality, flood, geocoding, elevation and model-specific endpoints).
What to watch next
- Announcements about new variables, model sources, or expanded APIs via the project blog and X (as suggested by the provider).
- Changes to commercial access terms, pricing, or API rate limits — not confirmed in the source.
- How the service performs under sustained high-volume use and any related enterprise offerings — not confirmed in the source.
Quick glossary
- API: Application Programming Interface; a set of HTTP endpoints that let applications request and receive structured data such as weather forecasts.
- AGPLv3: A strong copyleft open-source licence that requires making source code available under the same licence when software is run over a network.
- CC BY 4.0: Creative Commons Attribution 4.0 International licence; allows sharing and adapting material, including for commercial use, provided attribution is given.
- Mesoscale model: A weather model that operates at finer spatial resolution (typically ~1 km to a few kilometres) to capture local phenomena better than coarser global models.
Reader FAQ
Is the Open-Meteo API free to use?
Yes — the API is offered free for non-commercial use and does not require a key or registration.
Can I use Open-Meteo data in commercial products?
The data are licensed under CC BY 4.0, which permits commercial reuse of the data itself; commercial API access and high-volume use are recommended to be handled via a paid subscription.
Do I need an API key or account?
No account, API key, or credit card is required for the free non-commercial API.
Where is the source code hosted and under what licence?
The project code is available on GitHub and is released under the AGPLv3 licence.
How much historical data is available?
The Historical Weather API provides more than 80 years of hourly data at 10 km resolution.
Open-Meteo Home Features Pricing API Docs Free Weather API Open-Meteo is an open-source weather API and offers free access for non-commercial use. No API key required. Start using it now!…
Sources
- Open-Meteo is a free and open-source weather API for non-commercial use
- About
- open-meteo/open-meteo: Free Weather Forecast API for …
- Pricing
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