Life Expectancy Calculator
How long might you live? Answer a few quick lifestyle questions for an instant estimate. Everything runs in your browser — private and free.
Enter your age above to see your estimate.
Illustrative estimate for education and entertainment — not medical advice. Many factors shape real longevity; your doctor sees the full picture.
How it works
- Answer 10 quick questions — age, gender, country and everyday lifestyle habits.
- See your estimate instantly — your projected lifespan updates live.
- Read the breakdown — exactly which habits add or cost you years.
How the estimate is calculated
We start from your country’s average life expectancy (roughly 73 globally, up to 84 in the longest-lived countries), add 5 years for women to reflect the well-documented gender longevity gap, then adjust for your answers. Smoking is the biggest lever — from +2 for never-smokers down to −13 for heavy daily smokers — followed by exercise (up to +4), diet (+3 to −4), stress (+2 to −4), sleep, alcohol and family longevity. Every adjustment is shown in the breakdown, so nothing is a black box.
Frequently asked questions
How accurate is this?
It’s a rough illustration, not a prediction. Real longevity depends on genetics, healthcare, environment and luck — factors no short quiz can capture. Treat it as motivation, not a medical verdict.
Why does country matter so much?
Average life expectancy ranges from the mid-50s in the lowest-ranked countries to 84 in Japan and Switzerland, driven by healthcare, diet, environment and lifestyle norms. Your country’s average is the most honest starting point.
Is my data private?
Completely. All calculations happen in your browser; nothing is sent to any server.
Can lifestyle really add years?
Large population studies consistently link not smoking, regular activity, healthy diet, good sleep and moderate alcohol with extra years of life. Small daily choices compound.
Why do women get +5 years?
Across almost every country, women outlive men by roughly 4–6 years on average. We use +5 as a simple, transparent baseline.
Does this calculator work for children?
It’s designed for adults. Childhood mortality patterns and decades of future medical progress make long-range estimates for children especially uncertain — treat any number as a very rough illustration.
Why is US life expectancy lower than Western Europe?
The US averages around 78 years versus 81–84 in most of Western Europe, a gap researchers attribute to higher rates of obesity, drug overdoses, gun violence, uneven healthcare access and wider health inequality — not genetics.
Life expectancy by country
Where you live is one of the strongest predictors of how long you’ll live. The table below shows the approximate average life expectancy at birth for the countries in this calculator (rounded, based on WHO and World Bank data). Japan and Switzerland top the list at around 84 years, while the global average sits near 73.
| Country | Avg. life expectancy |
|---|---|
| Japan | 84 years |
| Switzerland | 84 years |
| Australia | 83 years |
| Italy | 83 years |
| Spain | 83 years |
| Canada | 82 years |
| France | 82 years |
| Germany | 81 years |
| United Kingdom | 81 years |
| China | 78 years |
| United States | 78 years |
| Brazil | 76 years |
| Mexico | 75 years |
| Global average | 73 years |
| Russia | 73 years |
| India | 68 years |
| Pakistan | 66 years |
| South Africa | 66 years |
| Nigeria | 54 years |
What affects life expectancy most?
Not all habits matter equally. Ranked roughly by impact on the average lifespan:
- Smoking — the single biggest lever. Heavy lifelong smokers die about 10–13 years earlier on average than never-smokers.
- Diet and weight — diets high in whole foods, vegetables and legumes are consistently linked with extra years; heavily processed diets with fewer.
- Physical activity — regular moderate exercise (even brisk walking) is associated with 3–4 extra years versus a sedentary life.
- Alcohol — heavy drinking shortens life; light-to-moderate drinking shows little effect either way in most large studies.
- Sleep — consistently sleeping 7–8 hours beats both chronic short sleep and very long sleep.
- Stress and social connection — chronic stress and loneliness are both linked with higher mortality; strong relationships protect.
- Healthcare access and environment — largely captured by the country baseline: clean air, safe water, vaccination and hospitals.
Sources and methodology
This calculator is an educational illustration, not a medical tool. Country baselines are rounded approximations consistent with figures published by the World Health Organization (Global Health Observatory) and the World Bank. Lifestyle adjustments are simplified magnitudes drawn from large population studies (e.g. research on smoking and mortality, physical activity cohort studies, and sleep-duration meta-analyses) — rounded for transparency rather than false precision. Individual outcomes vary enormously with genetics, healthcare and chance. For personal health decisions, talk to your doctor.