What it does
OpenWeather One Call API 3.0 returns a combined weather timeline through a REST endpoint. Its documented request supplies latitude, longitude, and an API key, with optional parameters to exclude response sections and select units. The product page describes current and forecast information, alerts, and historical weather data. One Call is one offering within OpenWeather's broader weather API catalog, and this record is limited to the 3.0 endpoint.
The API is useful when a client needs several weather intervals without composing a separate request for each response section. A typical call uses the documented /data/3.0/onecall endpoint with latitude, longitude, optional excluded sections, and the account's appid; the response can be trimmed to current, minutely, hourly, daily, or alert data that the application uses. The getting-started guide says keys are issued after signup and that usage limits are aggregated across keys and subscribed products at the account level. The One Call price page currently labels the model pay-per-call, with the first 1,000 calls per day free and additional calls charged; check the live plan details before projecting a larger workload.
Strengths
- A single documented endpoint can return multiple forecast and current-weather sections using latitude and longitude.
- The request supports excluding unneeded response sections and selecting standard, metric, or imperial units.
- The official pricing page publishes a daily free-call allowance and a pay-per-call rate for additional calls.
Watch out for
- An account and API key are required, and API use is counted against account-level limits shared across keys and subscribed products.
- The request requires coordinates; city-name conversion is handled by OpenWeather's separate Geocoding API.
Best for
- Applications that need current, forecast, and alert weather data for a known latitude and longitude.
- Dashboards or mobile products that want one request to assemble several weather intervals and omit unused data.
Sources
- One Call API 3.0 (Oct 25, 2026)
- How to start to work with Openweather API (Oct 25, 2026)
- Pricing (Oct 25, 2026)