Researchers have created a calculator that is capable of working out your fitness age.
According to the UK website, the calculator asks seven questions about users' lifestyle and physique to find out how well your body delivers oxygen to its cells - a measurement called VO2 max.
The scientists confessed that the device is not any exact science but is a "rough estimate of cardiorespiratory fitness", News.com.au reported.
For the study, lead researcher Ulrik Wisloff and his team got 5,000 people between 20 - 90 years old to run on a treadmill to the exhaustion point.