1 - Tom Baker (December 28, 1974-March 21, 1981) - 6 years, 2 months and 21 days
2 - Jon Pertwee (January 3, 1970-June 8, 1974) - 4 years, 5 months and 5 days
3 - David Tennant (December 25, 2005-January 1, 2010) - 4 years and 7 days
4 - Matt Smith (April 3, 2010-December 25, 2013) - 3 years, 8 months and 22 days
5 - Peter Capaldi (August 23, 2014-December 25, 2017) - 3 years, 4 months and 2 days
6 - William Hartnell (November 23, 1963-October 29, 1966) - 2 years, 11 months and 6 days
7 - Colin Baker (March 16, 1984-December 6, 1986) - 2 years, 8 months and 20 days
8 - Patrick Troughton (November 5, 1966-June 21, 1969) - 2 years, 7 months and 16 days
9 - Sylvester Mccoy (September 7, 1987-December 6, 1989) - 2 years, 2 months and 29 days
10 - Peter Davison (January 4, 1982-March 16, 1984) - 2 years, 2 months and 12 days
11 - Jodie Whittaker (October 7, 2018-present) - 2 years and 11 days
12 - Christopher Eccleston (March 26-June 18, 2005) - 2 months and 23 days
13 - Paul Mcgann (May 27, 1996) - 0 days