6.2 million viewers tuned in to watch Let's Kill Hitler, according to unofficial overnight figures.
The programme had a share of 28.7% of the total TV audience and was the most watched programme of the day on BBC One. The total included 1.02 million viewers who were watching on BBC One HD.
The X Factor on ITV 1 won the day with 10.6 million watching. Against Doctor Who ITV1 scored 5.4 million for All Star Family Fortunes.
Doctor Who's audience was steady throughout the episode, with an initial figure of 6.2 million rising to a peak of 6.3 million. With one day to come, Doctor Who currently stands at 17th for the week.
Final figures, which will be released in 8 days time, should see the final total rise considerably, when those who record the episode and watch it later are factored in.
On BBC Three 0.51 million watched Doctor Who Confidential.