How to use the relatedness coefficient calculator
Estimate the genetic relatedness of two relatives from the number of links in the family path between them. Enter number of links in the family path in the field above; the relatedness through one ancestral path are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “coefficient of relationship”, “how related am I to my cousin”, “relatedness by generations”, “calculate relatedness coefficient”, “find relatedness through one ancestral path”.
Formula
Variables
- n — Number of links in the family path
Worked example
With number of links in the family path = 4, the calculator gives relatedness through one ancestral path ≈ 0.0625 fraction; relatedness through one ancestral path ≈ 6.25 %.
Frequently asked questions
What is the relatedness coefficient calculator used for?
Estimate the genetic relatedness of two relatives from the number of links in the family path between them. It helps with questions such as “coefficient of relationship”, “how related am I to my cousin”, “relatedness by generations”.
What is the formula for the relatedness coefficient calculation?
Relatedness through one ancestral path (fraction) = 0.5^n. Relatedness through one ancestral path (%) = 100 × 0.5^n. Here n is number of links in the family path.
What inputs do I need for the relatedness coefficient calculator?
You need number of links in the family path. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the relatedness coefficient calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the relatedness coefficient result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.