LifeClock 120 asks us a series of questions about our lifestyle and habits and calculates our life expectancy. It has 120 years because we believe that humans can live a lot longer. If we can change our mindset lifestyle and our food choices. Aim to be active vital and healthy We may live to see 100 + years and be able to enjoy the rest of our lives and have enough puff to blow out 100 + candles.