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

Question

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 1

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

Looking at the API documentation, if you add &units=metric to your request, you'll get back celsius.

Answer 2

That appears to be kelvin, but you can specify the format you want returned for the temp, e.g.:

http://api.openweathermap.org/data/2.5/weather?q=London&mode=json&units=metric

or

http://api.openweathermap.org/data/2.5/weather?q=London&mode=json&units=imperial