The file attached contains a complete set of experimental data from biochar self-heating ignition of cubic basket experiments for a range of feedstock materials (Softwood, Wheat pellets and rice husks) produced in a kiln reactor at temperatures ranging between 350 and 800 °C. The experiments are all oven-basket experiments, and were carried out in a thermostatically controlled oven with thermocouples for measuring the ambient and sample temperatures. The data reported includes the dates of experiments, volume of samples being tested, oven ambient temperature, reactor production temperature, bulk density of the sample and if the sample ignited or not. There are 3 worksheets included, one per feedstock type. This data is in support of the journal paper: F. Restuccia, O. Masek, R. M. Hadden, G. Rein, Quantifying self-heating ignition of biochar as a function of feedstock and the pyrolysis reactor temperature, Fuel 236 (2019), pp 201-213 https://doi.org/10.1016/j.fuel.2018.08.141.