I have often heard that in World War Two the different nations varied greatly in strength. Some people I have heard have gone so far as to say a Soviet Tank Army is equal to a Panzer Division but I feel like this may be exaggerated. So I was wondering how would different nations infantry and tank divisions compare across different fronts.
This previous question has some good comparisons on the Chinese and Japanese divisions on the China front.
Hard to give a complete answer since the organizations of such units varied throughout the war often significantly. The strenght numbers changed quite a lot especially the Red Army tank formations saw a lot of changes. Before the war the Red Army was planning on having huge tank formations but this was scaled down over the first years of the war.
However it is true that the Red Army designation for their tank forces wasn't really comparable with other Armies. The tank corps for instance was merely a weaker tank division if compared with Wehrmacht counterpart. The tank numbers eventually were about 200 which is comparable to other armies divisions ( Normally a corps would consist of several divisions). A Soviet tank army would consist of several tank corps and could easily have 500+ tanks. In terms of numerical strenght a Soviet tank army was considerable bigger than a German Panzer Division. How this translated to the battlefield is a different story and depending on the Panzerdivision a tank army could be only equal in terms of impact on the battlefield. In general the Tank Army was a more powerful unit but like i said it depends.