Reptile Egg Incubation Calculators
Free hatch-date and gestation calculators for 15 commonly kept reptile species — snakes, lizards, turtles, and tortoises. Select a species below to calculate its expected hatch date and view temperature, humidity, and hatchling care guidance.
🐍 Snakes
🦎 Lizards
🐢 Turtles & Tortoises
Reptile Incubation Comparison Table
Incubation length across reptiles spans an enormous range — from 45 days for a Scarlet King Snake to as long as 300 days for a Panther Chameleon. Most reptiles are egg-layers (oviparous), but a few well-known species — boa constrictors, blue tongue skinks, and some chameleons — are live-bearers (viviparous), giving birth to fully-formed young instead.
| Species | Incubation / Gestation | Reproduction |
|---|---|---|
| Scarlet King Snake | 45 days | Egg-layer |
| Ball Python | 55–60 days | Egg-layer |
| Corn Snake | 55–65 days | Egg-layer |
| Russian Tortoise | 60–75 days | Egg-layer |
| Crested Gecko | 60–120 days | Egg-layer |
| Red-Eared Slider | 59–90 days | Egg-layer |
| Bearded Dragon | 55–75 days | Egg-layer |
| Blue Tongue Skink | 100–105 days | Live-bearer |
| Green Iguana | 90–120 days | Egg-layer |
| Boa Constrictor | 100–120 days | Live-bearer |
| Sulcata Tortoise | 90–120 days | Egg-layer |
| Monitor Lizard | 150–180 days | Egg-layer |
| Leopard Tortoise | 130–180 days | Egg-layer |
| Chameleon | 150–300 days | Egg-layer / live-bearer* |
*Veiled and Panther chameleons lay eggs; Jackson chameleons are live-bearers.
Egg-Layers vs. Live-Bearers
Most reptiles are oviparous (egg-laying) — the female lays eggs that then incubate externally, whether in a natural nest or an artificial incubator, before hatchlings pip and emerge. A smaller group of reptiles are viviparous (live-bearing) — the female retains developing young internally for the full gestation period and gives birth to fully-formed neonates, skipping the external incubation stage entirely. Boa constrictors and blue tongue skinks are two of the most commonly kept live-bearing reptiles.
How to Use These Calculators
Each calculator uses the formula Hatch (or Birth) Date = Lay/Ovulation Date + average incubation or gestation days for the selected species. Select your species above, open its calculator, and enter the lay or ovulation date to get an exact expected date along with a full milestone timeline.