A method is presented for calibrating a cantilever, such as a scanning probe microscope cantilever (SPM cantilever). The cantilever to be calibrated comprises at least a first and a second layer having a mutually different thermal expansion coefficient, the method comprising the steps of: controllably causing a temperature distribution along the cantilever, measuring a spatial state of the cantilever, computing a mechanical property from the observed spatial state caused by controllably changing the temperature. Also a calibration arrangement and a scanning probe microscope provided with the calibration arrangement are presented.