Open-Meteo
Free & Open alternative data provider · 1 listed dataset
Open-Meteo is an open-source weather-data service that provides forecast, historical, air-quality, marine, climate, and related information through web APIs. Its principal forecast interface combines numerical weather-prediction output from multiple national and regional providers behind a common request and response format.[1][2]
The public service permits limited non-commercial use without an API key, while subscriptions provide commercial-use rights and reserved capacity.[1][3] The server code is published under the GNU Affero General Public License, and the website states that API data are distributed under the Creative Commons Attribution 4.0 license.[1]
What It Does
Open-Meteo accepts geographic coordinates and requested variables, then returns current conditions or time series in formats intended for software use.[1][2] The forecast API supports hourly, daily, and selected 15-minute variables, including temperature, precipitation, humidity, pressure, cloud cover, wind, solar radiation, soil conditions, and derived measures.[2] It can also return CSV and spreadsheet output in addition to JSON.[1][2]
The service is an aggregation and delivery layer, not a national observing agency. Its inputs include models produced by organizations such as the European Centre for Medium-Range Weather Forecasts, Germany's DWD, the United States' NOAA, Meteo-France, the UK Met Office, and other meteorological services.[1][2]
Data And Methodology
Open-Meteo documents a default best-match option that selects an applicable high-resolution model for the requested location. It combines successive model runs into a continuous series and normalizes output to a common temporal structure.[1][2] A user may instead select individual models for comparison or model-specific processing.[2]
Forecast values are model outputs rather than direct station observations. Resolution, update frequency, forecast horizon, and available variables differ by provider and region.[2] The documentation also notes that some sub-hourly values outside covered regions are interpolated from hourly data.[2] These distinctions matter when the API is used for verification, operational decisions, or machine-learning training.
Products
Alongside the main forecast endpoint, Open-Meteo lists APIs for historical weather, archived forecasts, individual and previous model runs, ensembles, seasonal forecasts, climate projections, marine conditions, air quality, satellite radiation, geocoding, elevation, and floods.[2] Its historical layers serve different analytical purposes: reanalysis supplies long, spatially complete series, while archived forecasts preserve values as they were issued and can reduce look-ahead bias in retrospective work.[1]
The public homepage describes the interface as ordinary HTTP GET requests with query parameters and consistent variable names across live and historical products.[1] Self-hosting is possible from the published server source, but doing so requires the operator to obtain, process, and serve the upstream datasets and to comply with applicable licenses.[1]
Delivery And Pricing
The free endpoint requires neither registration nor an API key and is subject to published minute, hour, day, and month limits.[1][3] Open-Meteo states that this endpoint is for non-commercial use and has no uptime guarantee.[3] Paid plans use a customer endpoint and API key, include a commercial-use license, and run on reserved capacity with a stated uptime target.[3]
Plans are differentiated by monthly call budgets, access to selected historical and specialist APIs, support, and custom arrangements.[3] Because allowances and prices can change, applications should read the current pricing and license pages rather than treat a quoted plan figure as permanent. Attribution remains required under the stated data license.[3]
Landscape And Verification
Open-Meteo occupies a layer between primary meteorological model producers and applications that need a unified interface. Its value lies in normalization and convenient delivery; authority for a particular forecast model remains with the originating weather organization.[1][2] The Internet Archive independently records an archived copy of the service's public website, providing a dated external record of its presentation and availability.[4] No independent audit of forecast accuracy or service reliability was located in the reviewed sources, so those qualities should not be inferred from the breadth of documented coverage.
More datasets from Open-Meteo
Open-Meteo lists 1 datasets on this encyclopedia. The most representative listings:
More about Free & Open Data
Free & Open Data is one of the signal families covered by The Alternative Data Encyclopedia, with 36 providers and 322 datasets listed in the register. For how the signal is generated, its caveats and the compliance considerations, and the full provider list, see the category article.
Further reading
- How funds evaluate alternative data vendorsEvaluating alternative-data providers: research fit, provenance, historical timing, permitted use and the evidence needed for an informed purchasing decision.
- Open vs commercial alternative dataWhat free and open datasets can and cannot do: where public data rivals paid panels, where it cannot compete, and how open sources fit a professional research workflow.
- Alternative data for hedge fundsA practical guide to alternative data for hedge funds: team design, budget sequencing, infrastructure, vendor portfolio construction and the metrics that show whether the program creates investment value.
- Free alternative data sourcesThe practical list of free alternative-data sources for investors: public filings, official statistics, satellite and earth observation, on-chain data, web archives and open registries, what each covers, what it costs in engineering effort, and where free data falls short.