A MEMS-based Fourier Transform (FT) spectrometer is provided. According to an embodiment, the MEMS-based FT spectrometer is an FT infrared (FTIR) spectrometer. The FT spectrometer can include a beam splitter positioned to receive an incoming beam from a light source and split the incoming beam into a first sub-beam and a second sub-beam, a fixed mirror positioned to receive the first sub-beam from the beam splitter, a scanning MEMS mirror positioned to receive the second sub-beam from the beam splitter, and a photodetector, wherein a reflected first sub-beam from the fixed mirror and a reflected second sub-beam from the scanning MEMS mirror recombine at the beam splitter and become directed to the photodetector. According to one embodiment, the photodetector is a MEMS-based IR detector. In addition, the MEMS-based IR detector can be an un-cooled IR detector having a capacitive sensing structure.