About the casualties:
according to Boris Sokolov, the total number of Soviet-Mongol personnel who participated in all stages of the battle was about 125,000; given this, a cumulative casualty toll of 29,000 corresponds to a wear rate of just over 23%. Of course, combat units, especially ground troops, were disproportionately affected. Historian Maksim Kolomiets identifies
51,950 men among the latter by August 20, the day Zhukov's final offensive began - not including the Mongol People's Army. Zhukov states that from that date until the 30th Soviet troops took 9,284 casualties, excluding sick, and, of course, the losses of the Mongolians - broken down as 1,569 dead, 7,583 wounded, and 131 missing. Thus, during that time the attrition rate among the front-line troops was at least 18%. Probably most of these losses were incurred in the first half of the offensive phase, before the 23rd Division's resistance was broken and its remnants routed back toward Nomonhan in an attempt to avoid encirclement: the Soviet command reported 546 dead, 3,637 wounded, and 28 missing from August 20-22 alone, and the Japanese counterattack on the southern flank from the 24th to the 26th probably accounted for much of the remainder.
On the IJA side, out of all forces theoretically under the jurisdiction of 6th Army headquarters (including air units), the total wear rate was about 24% (26.5% including sick). However, this conceals the fact that from an administrative standpoint the bulk of the 6th Army consisted of units that were never thrown into battle, such as the 2nd, 4th, and 1st Divisions, and were only assigned to it at the very end of the conflict in the hopes of launching a counteroffensive. The troops that carried out the majority of the real fighting - the 23rd Division and elements of the 7th Division - suffered devastating casualties: 68% for the former (76.5% including ill), and 32.6% for the latter. Although the Soviet forces were badly bloodied, the Japanese, when it came to those formations at the point of contact, lost one division virtually destroyed and a second one crippled.