High fidelity—or hi-fi or hifi—reproduction is a term used by home stereo listeners and home audio enthusiasts to refer to high-quality reproduction of sound to distinguish it from the poorer quality sound produced by inexpensive audio equipment, or the inferior quality of sound reproduction that can be heard in recordings made until the late 1940s. Ideally, high-fidelity equipment has minimal amounts of noise and distortion and an accurate frequency response.

High fidelity or hi-fi is most commonly a term for the high-quality reproduction of sound or images.