We demonstrate temperature measurement of a sample attached to the end of a cantilever using cantilever magnetometry of solid air "contamination" of the sample surface. In experiments like our magnetic resonance force microscopy (MRFM), the sample is mounted at the end of a thin cantilever with small thermal conductance. Thus, the sample can be at a significantly different temperature than the bulk of the instrument. Using cantilever magnetometry of the oxygen paramagnetism in solid air provides the temperature of the sample, without any modifications to our MRFM apparatus. (C) 2003 American Institute of Physics.