Evolution without selection. Pure chance in sampling each generation makes allele frequencies wander — and in small populations, quickly fix or vanish.
Genetic Drift (Wright-Fisher)Live
chance changes allele frequencies
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Even with no selection, allele frequencies wander purely by chance as each generation is randomly sampled from the last. In small populations this genetic drift is fast and alleles quickly fix or vanish; in large populations it is slow. Each colored line is an independent population starting from the same frequency.
Reading this result: Over many replicates the fraction that fix an allele converges on its starting frequency p₀=0.5 — drift is directionless, but the odds of fixation equal where you began.
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How it works
The Wright-Fisher model builds each generation by randomly sampling alleles from the previous one. With no selection, frequencies still drift because sampling is random, and eventually every allele is either fixed or lost. Drift is powerful in small populations and negligible in large ones — a key force in evolution and conservation genetics. Each line is a replicate population.
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The math, the assumptions, real-world uses, or a code translation — explained for this exact simulation.
Is this genetic drift simulator tool really free?▾
Yes. Genetic Drift (Wright-Fisher) runs entirely in your browser using your device's own compute, so local use is free forever. You only pay Compute Tokens if you scale a job to the cloud.
Do I need to install anything?▾
No. Everything runs client-side in a modern browser — no downloads, no license, no account required to start.
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How accurate are the results?▾
The solver uses established numerical methods, but results are for research and educational purposes and should be validated against experiment or professional review before you rely on them.