Cohort Replacement Calculator
Whether each generation is replacing the one before it, at a fertility rate you set, and what that compounds to over three generations.
At a fertility rate of 2.2 a parent generation of 1.9 billion produces about 1.95 billion children — 4.8% growth per generation, which compounds to 2.18 billion after three.
Cohort Replacement Calculator
Frequently asked
Is the Cohort Replacement Calculator free?
Yes. Every tool on AlphaBetaMinds is free, needs no account and has no usage limit.
Does this tool store what I type?
No. It runs entirely in your browser. Your inputs are never sent to our server, and nothing is logged.
How accurate is it?
It uses the McCrindle generation boundaries (Gen Alpha 2010–2024, Gen Beta 2025–2039) and UN World Population Prospects vital rates. Sources and formulas are on our methodology page.
Can I use the result in an article or report?
Yes, with a credit and a link back to this page. See our terms of use for the full licence.
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