How much is a 1923 100000 mark worth today?

It might be worth something to a collector but it is worth nothing as currency. By the end of 1923 100,000 marks was worth less than 1 millionth of a US cent and Germany was issuing 1 trillion mark notes. People were burning money because it provided more heating than the coal a note such as yours would buy. The currency was changed in 1924.