a b s t r a c t Herein, we prove that self-heating effects occur in sensor films made of randomly oriented nanoparticles (electro-sprayed, drop-casted and paint-brushed films of carbon nanofibers). A 2-point calibration method, reliable enough to overcome the lack of reproducibility of low cost fabrication methods, is also proposed. Self-heating operation makes possible reaching temperatures up to 250 • C with power consumptions in the range of tens of mW. For certain low-temperature applications (<100 • C) typical power consumptions are as low as tens of W. The method is suitable to modulate the response towards gases, such as humidity, NH 3 or NO 2 . This approach overcomes the complex fabrication requirements of previous self-heating investigations and opens the door to use this effect in cost-effective devices.