How is the per-stat perfect chance calculated?

A stat is perfect when it is inherited from a parent and that inherited value happens to be a perfect one. The tool multiplies the chance a stat is among the inherited slots by the chance the inherited value is perfect, giving the per-stat probability.

Why does targeting more perfect stats get so much harder?

The chance that every target stat is perfect is the per-stat chance multiplied by itself once per target stat. Each extra perfect stat you demand multiplies the odds down, so a four- or five-stat perfect specimen is exponentially rarer than a two-stat one.

How do inherited slots change the odds?

More inherited slots mean each stat is more likely to come from a parent rather than a random roll, raising the per-stat perfect chance. Items that lock additional parent stats are the single biggest lever for cutting the attempts needed.

What is the fastest way to breed a perfect specimen?

Target fewer stats per generation and combine winners. Breeding a perfect two-stat parent and a perfect three-stat parent, then pairing them, reaches a five-stat result far faster than chasing all five in a single egg from imperfect parents.

Does EVE Online have creature breeding?

EVE Online's main game does not, but breeding-and-IV systems all share the same inheritance probability math. This calculator implements that model exactly, so you can set the total stats, inherited slots and parent quality to match whatever system you are playing.

EVE Online Breeding & IV Calculator

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Plan an IV breeding chain with real odds

Breeding for perfect stats is a probability problem that punishes guesswork — chasing too many perfect stats at once can mean hundreds of eggs. This calculator gives you the real per-stat and full-perfect odds, the expected attempts, and your chance of success over a set number of tries, so you can plan an efficient breeding chain. It runs entirely in your browser.

How it works

Each target stat is perfect only if it is inherited from a parent and the inherited value is a perfect one:

pPerStat = (inheritedSlots / totalStats) * (perfectParentStats / totalStats)

The chance that all your target stats land perfect in a single egg multiplies that per-stat chance once per target:

pPerfectAll = pPerStat ^ targetStats

Over many attempts the chance of at least one perfect offspring is the complement of failing every time:

P(at least one) = 1 - (1 - pPerfectAll)^attempts

Example and tips

Wanting three perfect stats from parents holding three perfects between them, with five of six stats inherited each egg, gives a modest per-egg chance — so 20 attempts might only land a perfect result some of the time. Two strategies cut the work sharply: use an item that locks more parent stats to raise inherited slots, and build up perfection in stages, breeding small perfect parents first and then pairing the winners. Targeting fewer stats per generation, then combining them, beats chasing everything in one egg every time.