Fancy wearing a watch that tells you how long you've got to live?

A Swedish inventor has designed a watch that calculates a person's life expectancy - and even counts down to the time they'll die.

Most would call it the 'death watch', but creator Fredrick Coltin calls it 'The Happiness Watch'.

He claims it'll help people make the most of their life and cherish the time they have left.

People enter information about their medical history, exercise and weight, then their age is deducted to predict a death date and the watch begins the countdown.

Tick-tock, tick-tock.