The discovery, made by scientists in the US, confirms a theory first proposed by Einstein – that clocks run faster the further away from the ground they are.
Although the concept has been accepted for many years, now the difference can be measured for the first time with astonishing accuracy.
Using a pair of the world's most precise clocks, physicists at the National Institute of Standards and Technology, Colorado, discovered that simply going upstairs will make you age faster.
If one of the clocks was moved just a foot higher, then it ran a little bit faster – albeit by a tiny fraction of a second.
So, taking just a couple of steps upwards will remove 90 billionths of a second to a 79-year lifetime.
By moving about 10 feet to the top of the stairs, you would age quicker by 900 billionths of a second.
And if you were to spend your life at the top of the 102-storey Empire State Building (1250 feet) you would lose 104 millionths of a second, said one of the researchers, James Chin-Wen Chou.
The experiments used "quantum logic" atomic clocks which can keep time to within one second over 3.7 billion years.
They prove the theory that clocks at higher elevations run faster because they are subject to less gravitational force.
A NIST spokesman admitted the phenomenon, called "gravitational time dilation", would not impact on people's lives.
"The difference is much too small for humans to perceive but it may provide practical applications in geophysics and other fields," he said.
The team's calculations will be used to improve technology used to measure the Earth and the gravitational field.
The findings are published in the journal Science.
The system does work in space rockets and aircraft as the forward movement offsets the height.