IEC 62951-1:2017(E) specifies a bending test method to measure the electromechanical properties or flexibility of conductive thin films deposited or bonded on flexible non-conductive substrates. Conductive thin films on flexible substrates are extensively used in flexible electronic devices and flexible semiconductors. Conductive thin films include any films deposited or bonded onto a non-conductive flexible substrate such as thin metal film, transparent conducting electrode, and thin silicon film. The electrical and mechanical behaviours of thin films on flexible substrates differ from those of freestanding films and substrates due to their interfacial interactions and adhesion between the film and substrate. The object of this standard is to establish simple and repeatable test methods for evaluating the electromechanical properties or flexibility of conductive thin films on flexible substrate. The bending test methods include outer bending test and inner bending test.