Life Table Calculator

Life Table Calculator. A life table is a demographic tool used in biology, ecology, and actuarial science to track survival and death rates across age groups within a population. Enter your initial population size, number of age intervals, and age-specific survival or mortality rates, then select your calculation method to get the life expectancy for your cohort. Secondary outputs include total deaths, mean survival rate, and mean mortality rate across all age classes. Also try the Simpson's Diversity Index Calculator.

Initial Population Size (l0) *

Starting population size at age 0

Number of Age Intervals *

Number of age classes to analyze

Age-Specific Survival Rates *

Survival rate for each age interval (comma-separated)

Age-Specific Mortality Rates (Optional)

Alternative to survival rates - will calculate survival if provided

Calculation Method *

Results

Life Expectancy

Total Deaths

Mean Survival Rate

Mean Mortality Rate

Results Table

What is a life table and why is it important?

A life table is a demographic tool that shows the probability of death and survival at each age for a population. It's essential for understanding population dynamics, insurance calculations, and conservation biology studies. See also our Competition Coefficient Calculator.

What does lx represent in a life table?

lx represents the number of individuals surviving to age x from an initial cohort. It shows how the population size decreases with age due to mortality.

How do I interpret the mortality rate (qx)?

The mortality rate qx is the probability that an individual of age x will die before reaching age x+1. Values range from 0 (no mortality) to 1 (100% mortality).

What's the difference between survival rate and mortality rate?

Survival rate is the probability of surviving from one age to the next, while mortality rate is the probability of dying. They are complementary: survival rate = 1 - mortality rate.

How is life expectancy calculated from a life table?

Life expectancy is calculated by summing the total years lived by the population and dividing by the initial population size. It represents the average lifespan of individuals in the cohort.

Can I use this calculator for animal populations?

Yes, life tables are commonly used in ecology and wildlife management to study animal population dynamics, breeding programs, and conservation efforts.

What if I only have mortality data instead of survival data?

You can enter mortality rates and select 'Based on Mortality Rates' as your calculation method. The calculator will automatically convert these to survival rates for the analysis. You might also find our find Effective Population Size (Ne) with Effective Population Size Calculator useful.