Improved temperature measurement and correction is provided for magnetoresistive sensor arrays. A linear coefficient of resistance vs. temperature is determined from one or more reference sensors in the array by measuring resistance of the reference sensors at known temperatures, which enables resistance measurements to be used to determine unknown temperatures in all sensors of the array. Double modulation leads to MR sensor outputs having center tones which can be used to correct temperature dependence in side tone MR signals. This correction can be according to a linear fit or a polynomial fit. Applications include biological assays requiring accurate temperature data, such as accurate determination of DNA melting curves.