Techniques are disclosed for measuring an amount of flicker produced by a light source. In one embodiment, a flicker measuring device includes a photo sensor to measure the amount of light produced by the light source, a dedicated processor to receive and process data from the photo sensor, a memory bus coupled to an analog-to-digital converter (ADC) and to a first memory, and a direct memory access (DMA) bus coupled to the ADC and to a second memory. In another embodiment, a flicker measuring system uses a light sensor, an associated circuit and a portable computing device (PCD), such as a smart phone, to measure an amount of flicker produced by a light source by sending an electrical signal from the light source and associated circuit via an audio output to an audio sub-system of the PCD, so that the PCD may calculate the flicker value.