The UTCI is a thermal comfort indicator which can assess outdoor thermal conditions and provide good predictions of thermal sensation votes depending on outdoor meteorological conditions.

You can calculate the UTCI of any location using the actual values of air temperature (Ta), mean radiant temperature (MRT), wind speed (va) and relative humidity (%RH).

To calculate for MRT using globe temperature:

UTCI Calculator
Download this Excel UTCI-Tool_Ver2 calculator.

Using the air temperature, wind speed, mean radiant temperature, relative humidity as inputs in the Excel UTCI -Tool Ver2 calculator, your calculated UTCI equivalent temperatures can be expressed in terms of thermal stress using the stress categories as shown on accompanying table:

UTCI chart


[1] Bröde, P., Fiala, D., Błażejczyk, K., Holmér, I., Jendritzky, G., Kampmann, B.. et al. (2012). Deriving the operational procedure for the Universal Thermal Climate Index (UTCI). International Journal of Biometeorology, 56(3), 481-494.

[2] Bröde, P., Krüger, E., Rossi, F., & Fiala, D. (2012). Predicting urban outdoor thermal comfort by the Universal Thermal Climate Index UTCI —a case study in Southern Brazil. International Journal of Biometeorology, 56(3), 471-480.

[3] Hardy, R. (1998). ITS-90 Formulations for Vapor Pressure, Frostpoint Temperature, Dewpoint Temperature and Enhancement Factors in the Range -100 to 100 °C. Proceedings of Third International Symposium on Humidity and Moisture; edited by National Physical Laboratory (NPL), London, 1998, pp. 214-221

[4] ISO. (1998). ISO 7726:1998 Ergonomics of the thermal environment — Instruments for measuring physical quantities (pp. 51). Geneva: International Standards Organisation (ISO).

[5] Vaisala (2013). Humidity Conversion Formulas – Calculation formulas for humidity. Helsinski, Finland (pp. 17).