How many people were members of the Nazi party during World War 2?
When it came to power in 1933, the Nazi Party had over 2 million members. Once in power, it attracted many more members and by the time of its dissolution it had 8.5 million members. Many of these were nominal members who joined for careerist reasons, but the party had an active membership of at least a million, including virtually all the holders of senior positions in the national government.(Source wikipedia)
The population of Greater Germany at its maximum extent (1941) was a little over 70 million. 8.5/70 is just over 12% of the population.