That's what actuarial tables are for. Assuming you're a 27 year old male living in the US, your chances of making it till you're 40 year old are around 97%. Thi

That's what actuarial tables are for. Assuming you're a 27 year old male living in the US, your chances of making it till you're 40 year old are around 97%. This number is based on population averages, so, if e.g. you don't do heavy drugs, your chances are way higher (given that overdose is a leading cause of death in young people).