We demonstrate high efficiency wavelength conversion via four wave mixing in amorphous silicon carbide ring resonators with a loaded quality factor of 70 000. Owing to the high quality factor and high nonlinearity of amorphous silicon carbide, −21 dB conversion efficiency is achieved with 15 mW pump power. Moreover, the thermo-optic coefficient (TOC) of amorphous silicon carbide is measured to be 1.4 × 10−4/°C at telecommunication wavelengths. Taking advantage of the high TOC, we demonstrate optical bistability in the silicon carbide ring resonator. This work presents amorphous silicon carbide as a promising platform for applications in optical signal processing.