Methodology & Data Sources
This page explains exactly how the Life Expectancy Calculator works, what data it uses, and how lifestyle adjustments are calculated.
Base Life Expectancy Data
The calculator uses the U.S. Social Security Administration 2022 Period Life Table — the same table used in the 2025 SSA Trustees Report. For each age and sex, the table provides "ex" — the expected additional years of life. When you enter your birth date, the calculator determines your precise current age, looks up ex for your age and sex, and adds that to your current age to produce your estimated lifespan.
SSA 2022 Period Life Table
Lifestyle Modifier Values
The lifestyle sliders apply evidence-based year adjustments to the base estimate. These are directional estimates drawn from population-level research — not individual predictions.
| Factor | Option | Years Added/Subtracted |
|---|
| Smoking | None | 0 |
| Smoking | Occasional | -3 years |
| Smoking | Daily | -10 years |
| Primary source. Smoking −10 years: Doll R et al., BMJ 2004 (British Doctors Study — 50-year follow-up). |
| Exercise | Sedentary | -3 years |
| Exercise | Light | 0 |
| Exercise | Active | +2 years |
| Exercise | Very Active | +3 years |
| Primary source. Exercise +2–3 years: Moore SC et al., PLOS Medicine 2012. |
| BMI | Healthy (18.5-24.9) | 0 |
| BMI | Underweight (<18.5) | -2 years |
| BMI | Overweight (25-29.9) | -1 year |
| BMI | Obese (30-34.9) | -3 years |
| BMI | Severely Obese (35+) | -7 years |
| Primary source. BMI: Global BMI Mortality Collaboration, Lancet 2016. |
| Alcohol | None or Light | 0 |
| Alcohol | Moderate | -1 year |
| Alcohol | Heavy | -5 years |
| Primary source. Alcohol: GBD 2016 Alcohol Collaborators, Lancet 2018. |
| Sleep | Under 6hrs | -3 years |
| Sleep | 6-8hrs | 0 |
| Sleep | 8+hrs | +1 year |
| Primary source. Sleep: Cappuccini et al., Sleep 2010 meta-analysis. |
| Stress | Low | +1 year |
| Stress | Medium | 0 |
| Stress | High | -3 years |
| Primary source. Stress: Kivimäki et al., BMJ 2012 (Whitehall II study). |
| Diet | Poor | -3 years |
| Diet | Average | 0 |
| Diet | Good | +2 years |
| Primary source. Diet: Sofi F et al., BMJ 2008 (Mediterranean diet meta-analysis). |
Important Limitations
These estimates are statistical averages from population data. They do not predict any individual's lifespan. Genetics, healthcare access, accidents, and countless other factors are not captured here. This tool is for educational and entertainment purposes only and is not medical advice.
Data Sources
SSA 2022 Period Life Table
CDC National Center for Health Statistics