Multi-mode fiber is used for transporting light signals to and from miniature fiber optic spectroscopy equipment (spectrometers, sources, and sampling accessories) and was instrumental in the development of the first portable spectrometer. Here we describe a compact spectrometer that achieves both high spectral resolution and broad bandwidth. By integrating a wavelength division multi-plexer with five multimode optical fibers, we have achieved 100 nm bandwidth with 0. An. Abstract: A standard multimode optical fiber can be used as a general purpose spectrometer after calibrating the wavelength dependent speckle patterns produced by interference between the guided modes of the fiber.