Methods, systems, and devices are described for wireless communications. More particularly, the described features relate to techniques for adjusting a modulation and coding scheme (MCS) to account for different airtime utilizations (available airtime actually utilized by a device for transmissions) resulting from different MCSs. In one example, a method for wireless communication may involve: determining a media access control (MAC) efficiency for a station of a plurality of stations based at least in part on a real-time multi-user (MU) physical protocol data unit (PPDU) length, a real-time physical layer service data unit (PSDU) length of each of the plurality of stations, and a modulation and coding scheme (MCS) of the station; adjusting a goodput estimate of the station using the MAC efficiency; and, adjusting the MCS of the station using the adjusted goodput estimate.