How do I calculate the temperature in celsius returned in openweathermap.org JSON?

javascript json units-of-measurement weather-api openweathermap
hitautodestruct picture hitautodestruct · Oct 20, 2013 · Viewed 45k times · Source

I'm getting the weather for a city using openweathermap.org.

The jsonp call is working and everything is fine but the resulting object contains the temperature in an unknown unit:

{
    //...
    "main": {
        "temp": 290.38, // What unit of measurement is this?
        "pressure": 1005,
        "humidity": 72,
        "temp_min": 289.25,
        "temp_max": 291.85
    },
    //...
}

Here is a demo that console.log's the full object.

I don't think the resulting temperature is in fahrenheit because converting 290.38 fahrenheit to celsius is 143.544.

Does anyone know what temperature unit openweathermap is returning?

Answer

T.J. Crowder picture T.J. Crowder · Oct 20, 2013

It looks like kelvin. Converting kelvin to celsius is easy: Just subtract 273.15.

And the briefest glance at the API documentation tells us that if you add &units=metric to your request, you'll get back celsius.

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