19 plus unknown thousands of years due to continuous time travel; head is 1055 years older than body.
From http://theinfosphere.org :
According to himself, Bender was originally constructed in 2998,
making him one year old when Fry met him in 2999, but several later
discoveries supports the theory that he was in fact born earlier.
Bender's memory as newborn is as a complete, fullgrown robot, but
events in "Teenage Mutant Leela's Hurdles" suggest that his current,
fullgrown body merely was the final stage, and it is possible that
Bender only remembers entering this final stage - what he considers
In season 6 episode "Lethal Inspection", it is revealed that Hermes
supervised Bender's construction before getting the job in Planet
Express, and is seen much younger than he must have been in the late
2990s. We also see that the state in which he was supervised -
reminiscent of a human baby - much differs from the one Bender
remembers from 2998. In "The Prisoner of Benda", it can be shown that
Hermes was already in the company in 2993, and thus Bender must have
been born in that year at least, and possibly even earlier. The events
in "Roswell that Ends Well" make his head 1055 years older than the
rest of his body. The incident in "Teenage Mutant Leela's Hurdles"
does largely not count as an aging or the opposite, and fans largely
regard his age to remain intact. In Bender's Big Score Film, Bender
travels back in time several times, though the amount of times is
unknown, the amount of Benders that appear at the end, may suggest at
least a couple of thousand times. Given how many of these travels
seems to be between 1000 to 5000 years in the past (from about 3007),
an educated guess would make him at least a million years old, but
probably more. An alternative theory could suggest when the time
duplicates explode at the end of the first film, Bender is the same
age he was at the end of the original run plus 995 years, as the
Bender that went back 995 years in time to kill Fry is presumed to be
the original and therefore wouldn't expire like the rest of them.
In the comic, "Rust in Peace", it is revealed that Bender, due to too
much time travelling, must be inserted into a renewed unit. Farnsworth
determines his age to be 27,203 before moving him to his new body. But
27,203 seems a lot less than what would be a quick educated guess.
27,203 would require Bender to have gone at least about a thousand
years back each time and only gone 27 times, or instead gone more
years back and done fewer than 27 times. But regardless of the ordeal,
the amount of Benders appearing at the end of Bender's Big Score seems
to contradict this fact. The event in the comic is thus not considered