This paper presents a field programmable lab-on-a-chip (FPLOC) with microfluidics actuation, droplet location/ category readback, built-in-self-test (BIST), and bioassays detection. This FPLOC is composed of 1,800 MEDA microelectrodes and integrates a set of microfluidic operations to perform droplet moving/cutting/mixing. Besides, capacitive sensing circuits are considered for system automation, droplets classification, malfunctioning microelectrodes and surface flatness testing, and biomedical detection. Implemented in 0.35μm standard CMOS process in 7.4mm2, the FPLOC demonstrates microfluidic operations under 25V at 1KHz, 1.3fF resolution for droplet location/category/chip BIST maps readback at 1MHz, and 0.34fF sensitivity of capacitive measurement window for biomedical detection at 1KHz.