Yes, HDMI 2.1 cables (and therefore 8K HDTV cables) are backward compatible with older HDMI devices (HDMI 2.0, 1.4, etc.). If your TV or source does not support 8K, the cable will still function at the maximum capability of your devices. However, to truly benefit from 8K and the new features of HDMI 2.1, all your devices (source, cable, display) must be 8K and HDMI 2.1 compatible.