My Reptile Atlas
by Ballpark Reptiles
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Crested Gecko genetics calculator

Pick what each parent carries and see every hatchling the pairing can produce, with the odds for each. Free, no signup, and it covers all 23 proven crested gecko genes.

Crested geckos have a small number of proven single-gene traits and a great many line-bred ones. This calculator covers the proven genes and is honest about the rest.

♂ Male

TRAITS CARRIED
Nothing selected — treated as a normal.
BASE COLOUR
INCOMPLETE DOMINANT
RECESSIVE
DOMINANT

♀ Female

TRAITS CARRIED
Nothing selected — treated as a normal.
BASE COLOUR
INCOMPLETE DOMINANT
RECESSIVE
DOMINANT

Predicted offspring

Add traits to one or both parents to see the odds.
Keep the pairing instead of re-typing it

My Reptile Atlas saves this against the two animals, then tracks the clutch through incubation and shows you how the real hatchlings compared to these odds. Free for up to 20 animals.

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What this calculator can and can't tell you

  • Frappuccino is not a gene. It's what you call an animal carrying both Cappuccino and Lilly White, so pick those two and the calculator names the result for you.
  • Lilly White has a lethal super. Two Lilly Whites give a 25% chance of a homozygous hatchling that won't survive the week. The row is shown, and flagged, because pretending otherwise would hide a quarter of the clutch.
  • Super Cappuccino is not lethal, but Morphpedia records reduced nostril size and spectacle eye in the super form.
  • Black Base, Yellow Base and Red Base share one locus, so an animal can carry at most two of them and can never be, say, Black Base and Yellow Base both.
  • Super Dalmatian isn't a super in the genetic sense. It describes how heavily spotted an animal is — five spots is a Dalmatian, a hundred is a Super Dalmatian — and it's the same gene either way, so there's one Dalmatian to pick and no separate super to breed for.
  • Harlequin, flame, cream and the rest of the pattern and colour traits are line-bred. They're real and they sell, but they don't segregate on a Punnett square, so no honest calculator will give you a percentage for them.

The genes it covers

Every trait MorphMarket Morphpedia lists as recessive, incomplete dominant or dominant, grouped by how it inherits.

INCOMPLETE DOMINANT
Lilly White · lethal superCappuccinoSableEmpty BackMonochromeSnowflakeSoft ScaleTangerineWhite Wall
RECESSIVE
AxanthicObscurial AxanthicPatternlessPhantomSuper Stripe
DOMINANT
DalmatianHypoOrange PatterningPinstripeTigerWhite Patterning
BASE COLOUR — ONE LOCUS, 3 ALLELES
These share a locus, so an animal carries at most two of them and never all three.
Black BaseYellow BaseRed Base

Traits no calculator can predict

MorphMarket Morphpedia classes these as polygenic or structural. They're real traits and they set prices, but they don't sit on a single gene, so no Punnett square predicts them. Anything quoting you a percentage for harlequin or flame is guessing.

Bi-colorBlushingBrindleBuckskinChevronCluster SpotsCold FusionCreamCreamsicleCrownedDrippyExtreme HarlequinFlameFringingFurredHalloweenHarlequinInk SpotKneecapsLavenderOil SpotOliveOrangePortholesQuad-stripeSolid BackTri-colorWhite Tip

What does work for these is records: pair the same two animals for a few seasons and your own hatch data tells you far more than any average could. That's what My Reptile Atlas is for.