We fabricated 13 440 molecular electronic devices using different lengths of alkanethiol self-assembled monolayers and performed statistical analyses on the histograms of the electronic transport properties of the alkanethiols. The statistical analysis provides criteria for defining 'working' molecular electronic devices and selecting 'representative' devices. The yield of the working alkanethiol devices was found to be ∼1.2% (156 out of 13 440 devices) and average transport parameters such as current density, transport barrier height, effective electron mass and tunnelling decay coefficient were obtained from the statistically defined working molecular electronic devices. From the length-dependent tunnelling and temperature-variable current–voltage characteristics of the working devices, the alkanethiol molecular devices showed typical tunnelling transport. However, the statistical consideration for determining working molecular devices should be carried out prior to these characterizations or detailed analysis on them.