Tool · for breeders

Inbreeding (COI) calculator over the Dogerra registry

300,000+ dogs — we calculate from real pedigrees, not your manual input. Pick a pair — get COI in seconds.

Dogerra Registry · read-time calculation

Pick a pair

Sire

Dam

How to read COI

< 5% — low risk
5–10% — watch closely, usually acceptable for the breed
> 10% — elevated risk — worth consulting a geneticist

Not medical advice. The breeding decision rests with the breeder and vet.

Free · go deeper

Go deeper: 10 generations, all common ancestors, PDF report

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What is COI, and why 5 generations isn't enough

The inbreeding coefficient (COI) is the probability that two copies of the same gene in an offspring were inherited from a common ancestor. It's computed with Wright's path method: the closer and more numerous the shared ancestors of a pair, the higher the COI. Dogerra doesn't calculate COI from your manual entry — it uses the real pedigree already in the registry, resolved automatically.

Honestly: a short pedigree (few known ancestors) UNDERESTIMATES COI, never overestimates it — a missing ancestor can't reveal a relationship that isn't visible. That's why the depth of the calculation and the pedigree's completeness at that depth are always shown next to the number. A deeper, fuller calculation (10 generations) is available in the Dogerra cabinet.

More tools

Pedigree builder →Breed registry →For breeders →

Read-time calculation from the Dogerra Registry — the number isn't stored in advance, it's computed on the fly from registry data.