Freitas, TT, Pereira, LA, Alcaraz, PE, Azevedo, PHSM, Bishop, C, and Loturco, I. Percentage-based change of direction deficit: a new approach to standardize time- and velocity-derived calculations. J Strength Cond Res 36(12): 3521–3526, 2022—Change of direction (COD) efforts are crucial in team sports, and an extensive body of research has been devoted to investigating this complex and multifaceted skill. Most studies have assessed players' ability to change direction by reporting completion time or average velocity in different COD tasks. However, it has been argued that these variables may not accurately portray an athlete's true capability to quickly change direction. In this context, new metrics such as the COD Deficit (CODD) have been proposed to provide complementary information on the efficiency to change direction. The current literature presents 2 different CODD computations: time-derived and velocity-derived calculations. Despite both being consistent and representing the same phenomenon, the decision of using one or the other may produce different outcomes, thus influencing coaches' decisions and training strategies. To overcome this issue, we propose a new approach to the computation of the CODD, based on the difference in percentage between linear sprint and COD abilities, in an attempt to standardize the estimation of this variable and simplify the evaluation of COD performance.