How does the Destiny Knot change the odds?

Without a Destiny Knot, 3 of the 6 offspring stats are inherited from the parents; with one, 5 are inherited. More inherited slots means a higher chance that a parent's perfect IV is passed down, which dramatically raises your odds when parents already hold those perfects.

What does the per-stat probability mean?

It is the chance one specific target stat ends up at 31 in the child, combining the chance it was inherited from a perfect parent and the small chance a random roll lands on 31 (1 in 32). The all-stats figure multiplies these across your target stats.

Why do average eggs and confidence eggs differ?

Average eggs is the mean of a geometric distribution (1 divided by the per-egg chance). Confidence eggs is how many you need so the probability of at least one success reaches your target, which is higher than the average because outcomes are random.

Is the independence assumption accurate?

Treating each target stat as independent is a close approximation that slightly understates odds in some inheritance edge cases, but it is accurate enough for planning how many eggs to hatch and which parents to invest in.

How do I maximise my odds?

Use two parents that are each already perfect in your target stats and always equip a Destiny Knot. That combination raises the inherited slots and the per-stat hit rate at the same time, collapsing the egg count needed.

Dota 2 Breeding & IV Calculator

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Breeding for a perfect-IV specimen is a numbers game, and guessing how many eggs you will need wastes hours. This calculator models inheritance and random rolls to give you a realistic per-egg chance, an average egg count, and the number of eggs to hatch before you can be confident of a success.

How it works

For each target stat, the child reaches a perfect 31 IV either by inheriting it from a perfect parent or by a lucky random roll:

inheritedFrac = destinyKnot ? 5/6 : 3/6
pInherit      = inheritedFrac × (perfectParents / 2)
pRandom       = (1 − inheritedFrac) × (1/32)
pPerStat      = pInherit + pRandom
pAllTargets   = pPerStat ^ (number of target stats)
averageEggs   = 1 / pAllTargets

Eggs for a confidence target solve 1 − (1 − p)^n ≥ C for the smallest whole number of eggs n.

Example and tips

Targeting 2 perfect stats with both parents perfect and a Destiny Knot gives a per-stat chance near 41.7% plus the small random term, so roughly a 1-in-5 chance per egg and about 27 eggs for 90% confidence. Always breed from parents that already hold your target perfects — every parent perfect you add is the single biggest reduction in the egg count.