Life Expectancy Calculator

Estimate remaining life expectancy adjusted for modifiable lifestyle factors.

About Life Expectancy Calculator

Adjustments here reflect population-level associations rather than individual causation, and they are not independent of one another. Smoking carries by far the largest single association of the factors included. Life expectancy at a given age exceeds life expectancy at birth, because having survived to that age already removes early mortality from the calculation.

Formula

Life Expectancy

Projected expectancy = population baseline adjusted for sex and modifiable factors

population baseline: Life expectancy at birth for the relevant population
modifiable factors: Smoking, activity and body composition, with published associations

Worked example

With the default values below, Life Expectancy Calculator returns Projected Life Expectancy of 84.6. Change any input above and every figure here is recalculated in your browser.

Inputs used

Current ageaccepts 18–100 years: 45 years
Sexone of Male, Female: Female
Population life expectancy at birthaccepts 50–100 years: 81 years
Current smokerone of Yes, No: No
Weekly exerciseaccepts 0–25 h: 3 h
Body mass indexaccepts 14–50 kg/m2: 24 kg/m2

Results

Projected Life Expectancy: 84.6 years
Remaining Years: 39.6 years
Net Lifestyle Adjustment: 2.10 years
Years Associated With Not Smoking: 0.00 years
Years Associated With Exercise Level: 2.10 years

Step by step

1Values used
2Life Expectancy
3Projected Life Expectancy= 84.6 years
4Remaining Years= 39.6 years
5Net Lifestyle Adjustment= 2.10 years
6Years Associated With Not Smoking= 0.00 years
7Years Associated With Exercise Level= 2.10 years

Assumptions and limits

The result is derived only from the 6 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax or compounding frequency into account.
Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
This reproduces a published formula for educational and reference use only. It is not a diagnostic tool, does not account for individual clinical context, and must not be used to make or change treatment decisions. Clinical assessment by a qualified healthcare professional is always required. This is a rough educational illustration of population associations, not a personal prognosis. It cannot account for genetics, medical history or circumstances. Do not use it for financial, insurance or medical planning; consult qualified professionals instead.
This is an estimate for general information and not professional medical advice. See the full disclaimer for the limits that apply to this kind of calculator.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

This reproduces a published formula for educational and reference use only. It is not a diagnostic tool, does not account for individual clinical context, and must not be used to make or change treatment decisions. Clinical assessment by a qualified healthcare professional is always required. This is a rough educational illustration of population associations, not a personal prognosis. It cannot account for genetics, medical history or circumstances. Do not use it for financial, insurance or medical planning; consult qualified professionals instead.

Frequently Asked Questions

How is Life Expectancy calculated?

Projected expectancy = population baseline adjusted for sex and modifiable factors Adjustments here reflect population-level associations rather than individual causation, and they are not independent of one another. Smoking carries by far the largest single association of the factors included.

Why does Life Expectancy matter?

Life expectancy at a given age exceeds life expectancy at birth, because having survived to that age already removes early mortality from the calculation.

What values do I need to enter?

This calculator takes 6 inputs: Current age, Sex, Population life expectancy at birth, Current smoker, Weekly exercise, Body mass index. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.