average players will range from around 3.5-4k, while slightly better players will range from 4-4.8k. highest solo mmr ive ever seen is rtz on 6.3k (dropped back to 6k now iinm). dendi, sing2x, fata is all around 6k+ too.

do note that for whatever reason, sea players DO have a slightly lower mmr than other regions and games are slightly harder on the higher end spectrum of the mmr. to take as an example, one of my friend who has ~5k mmr on sea has managed to increase his mmr to 5.5k after he started to play on use/usw/euw servers. i have never heard of anyone having more than 5.7k mmr on sea.

in ranked game counts after first blood