The total release of xenon-133 from the Fukushima Dai-ichi nuclear power plant accident

► We determine the total release of xenon-133 from the Fukushima nuclear accident. ► We used global measurements and a box model, as well as dispersion model estimates. ► Total 133Xe release is about 14.2-19 EBq, more than Fukushima 133Xe inventory. ► Additional release of iodine-133 and decay into 133Xe needed to explain results.