A nanoscale thermal anemometry probe (NSTAP) has been developed to measure instantaneous fluid velocity at ultra-small scales. The sensing length of the current probe (∼80 μm) is and order of magnitude smaller than presently available commercial hot-wire anemometer probes (TSI Inc, Dantec Inc). The sensing element is a freestanding nanowire 100 nm × 1μm × 60 μm. suspended between two current-carrying contacts. The probe is constructed using standard semiconductor and microelectromechanical systems manufacturing methods. The increased surface area to volume ratio of the metallic nanowire in comparison to conventional probes yields a device that not only has a higher spatial resolution but is also more sensitive and rapid in its response to changing flows.