And just what would you do if you knew exactly how much time you have to live?
A new watch dubbed "Death Watch" claims to be able to tell you how much time you have left on Earth, and then count down for you.
But is it too macabre or does it actually encourage wearers to live life to the fullest?
It's called Tikker: the happiness watch. But some call it the death watch that counts down your life.
"It's a little morbid. I don't know if i'd want to know," said Ray Kosakowski.
First, it gives you a death date, based on factors like your age, diet, and whether or not you smoke and exercise.
Then it counts down the days, hours, minutes, you have left to live.
"Are you kidding me? Who wants to know, I want to live today, enjoy life," said Elizabeth Fischer.
But the watch is supposed to remind you of just that.
"When you're dead, nothing really matters so what matters is being alive," said Tikker founder Fredrik Colting.
"I don't want to know when i'm gonna go, and I would not pay money to have a countdown of if it either," said Ellen Ward.
The watch is $59, available next April, if the company raises the $25,000 it needs on Kickstarter. But it's not the first calculator of death, there are all kinds of death clocks online.
It's impossible to medically predict an accurate death date, and the creator of the Tikker watch admits it's not accurate, but he said that's not the point.
"The whole point with Tikker is to see the big picture and realize one day and within I am certain amount of years, I will die, well I'm here now," said Colting.
Research shows the older we get, the less we sweat the small stuff. As the author of two best-selling books on happiness, Gretchen Rubin says the watch may be a good reminder.
"Older people know time is short so they don't spend time on things that aren't important to them and they make time for the people and activites they love so their lives become happier," said Rubin.
The concern, of course, is that it'll convince someone to say, I'm going to live another 50 years, why quit smoking?
Again, the watch does not give an accurate prediction of how much time you have left, but it can tell you what time it is right now.