10 Oldest Characters In The Doctor Who Universe
9. The Doctor
Estimated Age: Over 2,000 years.
The Doctor is one of the only characters in the show who routinely states how old they are. Whether it's the Fourth Doctor telling Sarah Jane Smith that he's "something like 750", or the Ninth Doctor telling Rose Tyler that he's nine hundred, the fact that the Doctor does this means that we can put a pretty solid number on how old the current incarnation, Thirteen, really is.
In Series 10's Smile, the Twelfth Doctor tells Nardole that he's "over two thousand years old", and since this is one of the last firm numbers that the Doctor actually gave, we know that they can't be much older than this. In Fugitive Of The Judoon, Thirteen tells Ryan that she's lived for "thousands of years", so everything lines up.
Now, we know what you're thinking: what about the Timeless Child? Doesn't this mean that the Doctor pre-dates Time Lord society, making them potentially billions of years old? Well, yes, technically, but since the Doctor only became "the Doctor" around the time of the Hartnell incarnation - y'know, the rogue Time Lord who started travelling the universe in a stolen TARDIS - then there's an argument to be made that the Doctor we all know and love has only existed for a couple of thousand years.
And no, the Heaven Sent years don't count either!