Longevity, quantified — by an actuary
Your actuarial age, from real life tables — not a death-clock guess.
Most “how long will I live” tools are a scoring gimmick with a quote form attached. This one starts from the 2021 U.S. period life table and adjusts it with peer-reviewed hazard ratios — every number cited, the maths shown in full, nothing sold in the results.
The baseline is the published NCHS 2021 U.S. period table — the same source class actuaries use, not a points-add-up quiz.
5 grade-A factors plus graded B factors, each a published hazard ratio translated into years — with the paper linked.
You get a point estimate and a visible range, capped where the literature caps it. We under-promise on purpose.
The evidence directory
View all →What actually moves life expectancy, in years, with the confidence honesty the podcasts skip.
The single most reliable dial you control: moving from unfit to fit buys years, and the biggest jump is off the bottom of the distribution.
≈ +4 years for the sedentary→fit shift, smaller with age
The largest single modifiable mortality effect we know of, and one of the few where the recovery on quitting is almost as dramatic as the damage.
~10 years lost by current smokers; most recoverable if you quit before 40
A J-shaped mortality curve where the cost of high BMI is real and graded, and the apparent benefit of being slightly heavy is mostly sick people who lost weight.
J-shaped; roughly −2 to −8 years across the obesity bands vs normal BMI
A U-shaped curve where both ends cost you, but the long-sleep arm is largely sick people sleeping more, not sleep making them sick.
U-shaped; short and long sleep each cost ~1–2 years
Why trust an actuary on this?
Predicting how long people live is the actuarial day job. The longevity space is full of biologists and hype merchants; almost nobody writes it from the seat that actually prices mortality for a living. About the author →