# open-meteo/open-meteo

Free Weather Forecast API for non-commercial use

Repository: https://github.com/open-meteo/open-meteo
Canonical: https://ross.abutalabs.com/products/open-meteo
Homepage: https://open-meteo.com
Language: Swift
License: AGPL-3.0
License Family: copyleft
Topics: weather-api, weather, weather-forecast
Last push: 2026-08-26T19:51:58+00:00

## Health v2 (maintenance only)
Score: 67/100 (v2, computed 2026-09-03T02:20:16.233290+00:00)
- activity 99, release rhythm 8, longevity 100
- inputs: {"age_days": 1896, "days_push": 7, "days_rel": 610, "gap_med": null, "n_releases_24m": 1}
- flags: none
- formula: round(0.45*activity + 0.35*rhythm + 0.20*longevity); archived -> min(score, 10)

## Adoption (not part of the score)
Stars 6093, forks 414 (observed 2026-08-28T04:09:34.985073+00:00)

## What it is
Open-Meteo is an open-source weather API service that aggregates numerical weather prediction models from 15+ national weather services into a fast, key-free JSON API. It offers forecasts up to 16 days, historical reanalysis back to 1940, and specialized APIs for air quality, marine, flood, geocoding, and elevation data, and can be self-hosted via Docker.

## Use cases
- get weather forecast data for my app without an api key
- fetch historical weather data since 1940 for climate analysis
- self-host a weather api server
- compare weather model forecasts from different national services
- get air quality and marine weather data via api
- build a weather app with hourly forecasts
- train bias-correction models on archived forecast runs
- geocode city names to coordinates for weather lookups

## When to choose
- you need free weather data for non-commercial use with no sign-up or API key
- you want high-resolution forecasts (down to 1 km) from multiple national weather models
- you need long historical weather time series (ERA5 reanalysis from 1940)
- you want to self-host the API with Docker or Ubuntu packages
- you need low-latency JSON responses with CORS support

## When to avoid
- you need a commercial-use licence without a paid subscription
- you require guaranteed 99.9% uptime SLAs on the free tier
- you need weather data outside the coverage of open national weather models
- you want a SDK-wrapped or GraphQL interface rather than plain HTTP GET JSON

## Facets
- artifact type: service
- maturity: active
- function: api-framework, http-server, data-science, etl, self-hosted
- domain: weather, apis, self-hosted
- platform: self-hosted
- tags: weather-api, weather-forecast, historical-weather, era5, geocoding, air-quality, no-api-key, json-api, data-engineering, linux, docker, web-server, swift

## Member repositories
- open-meteo/open-meteo (main) score 67

## Provenance
- Observed fields: from GitHub, fetched 2026-08-28T04:09:34.985073+00:00.
- Health v2: computed from the inputs above; adoption is never an input.
- Inferred fields (summary, facets, guidance): AI-extracted, prompt v1, taxonomy v1, on 2026-08-29T17:48:17.417018+00:00, confidence not recorded.
  - readme: https://github.com/open-meteo/open-meteo (fetched 2026-08-28T04:09:34.985073+00:00, sha 9b0b0248c499)
  - homepage: https://open-meteo.com (fetched 2026-08-29T08:44:59.432177+00:00, sha 128aad4c18dc)
  - site_page: https://open-meteo.com/en/features (fetched 2026-08-29T08:44:59.434945+00:00, sha eddaba15fb25)
  - site_page: https://open-meteo.com/en/docs (fetched 2026-08-29T08:44:59.440506+00:00, sha 2bd7ad376335)
  - site_page: https://open-meteo.com/en/docs/historical-weather-api (fetched 2026-08-29T08:44:59.443092+00:00, sha 94a37f1ff989)
  - site_page: https://open-meteo.com/en/docs/historical-forecast-api (fetched 2026-08-29T08:44:59.445672+00:00, sha 7ab444f4cb5a)
  - site_page: https://open-meteo.com/en/docs/previous-runs-api (fetched 2026-08-29T08:44:59.448600+00:00, sha 35a50003304d)
  - site_page: https://open-meteo.com/en/docs/single-runs-api (fetched 2026-08-29T08:44:59.450817+00:00, sha d51643b31501)
  - site_page: https://open-meteo.com/en/about (fetched 2026-08-29T08:44:59.452971+00:00, sha b10327522092)
  - site_page: https://open-meteo.com/en/pricing (fetched 2026-08-29T08:44:59.437419+00:00, sha 6817cf814bbd)
- Data as of 2026-08-30T08:39:29.467469+00:00.