Reptile Nutrition Calculator

Feeding guide for bearded dragons, geckos, and turtles. Calculate insect vs vegetable ratios for your reptile.

Feeding guidelines for common pet reptiles.

About This Calculator

Replicate a natural diet with the Reptile Nutrition Calculator. From insectivorous geckos to omnivorous bearded dragons, providing the right balance of protein and greens is essential for reptile health. Just as humans balance their macronutrient intake, reptiles need species-appropriate ratios to thrive.

Metabolic Bone Disease (MBD) is the most common nutritional disorder in captive reptiles, caused by calcium deficiency or improper calcium-to-phosphorus ratios. Prevention requires proper UVB lighting, calcium supplementation, and understanding your reptile's specific dietary needs. A 2:1 calcium-to-phosphorus ratio is ideal for most species.

Reptile nutrition changes dramatically with age. Juvenile bearded dragons need 80% insects for growth, while adults thrive on 80% vegetables. This transition typically occurs around 12-18 months of age. Feeding an adult dragon like a juvenile leads to obesity and liver problems.

Gut Loading & Supplementation

Gut Load: Feed insects nutritious food 24-48 hours before offering
Calcium: Dust insects with calcium powder at every feeding (growing reptiles)
Vitamin D3: 2-3x per week if no UVB lighting; 1x weekly with UVB
Multivitamin: 1x per week for variety

Reptile Diet Reference Chart

SpeciesDiet TypeJuvenile RatioAdult RatioFrequency
Bearded DragonOmnivore80% insects / 20% veg20% insects / 80% vegDaily
Leopard GeckoInsectivore100% insects100% insectsDaily → Every other day
Crested GeckoFrugivore/OmnivoreCGD + insectsCGD + occasional insectsEvery other day
Ball PythonCarnivorePinky/fuzzy miceRats (body width size)Every 7-14 days
Red-Eared SliderOmnivore70% protein / 30% veg25% protein / 75% vegDaily → Every 2-3 days
Blue-Tongue SkinkOmnivore50% protein / 50% veg40% protein / 60% vegEvery 2-3 days

Practical Example

For an adult bearded dragon: Offer a large salad of collard greens, squash, and bell peppers daily (80% of diet). Add 10-15 calcium-dusted crickets or dubia roaches 3x per week (20% of diet). Dust with vitamins once weekly. Occasional treat: blueberries or mango (once weekly max).

Safe Feeder Insects

  • Best staples: Dubia roaches, crickets, black soldier fly larvae (high calcium)
  • Occasional: Mealworms, superworms (high fat, use sparingly)
  • Avoid: Fireflies (toxic!), wild-caught insects (pesticides)

Reptile Feeding Tips

  • Never feed prey larger than the space between your reptile's eyes
  • Remove uneaten insects—crickets can bite sleeping reptiles
  • Provide fresh water daily; some species only drink moving water
  • Fast reptiles 24-48 hours before handling after large meals

Scenario Comparison: Diet by Species and Age

Species + AgeInsectsVegetablesFeeding Frequency
Juvenile Bearded Dragon80%20%3x daily
Adult Bearded Dragon20%80%1x daily
Leopard Gecko (any age)100%0%Daily to every 2 days
Adult Red-Eared Slider25% protein75%Every 2-3 days

Common Reptile Feeding Mistakes to Avoid

  • Not gut-loading feeder insects: Crickets and mealworms are nutritionally empty unless fed vegetables 24-48 hours before offering to your reptile.
  • Skipping calcium supplementation: Without calcium dusting, reptiles develop Metabolic Bone Disease (MBD)—the #1 preventable reptile illness.
  • Feeding adult dragons like juveniles: Adult bearded dragons need 80% vegetables, not 80% insects. Overfeeding protein causes obesity and gout.
  • Using only one type of feeder: Variety is essential. Rotate between crickets, dubia roaches, and occasional worms for complete nutrition.

Reptile Nutrition Benchmarks (Vet Standards)

RequirementBearded DragonLeopard GeckoAquatic Turtle
Calcium:Phosphorus ratio2:12:12:1
Calcium dusting frequencyEvery feeding (juvenile)Every feeding2-3x weekly
Vitamin D3 (with UVB)1x weekly1x weekly1x weekly
Feeder size ruleWidth between eyesWidth between eyesHead size

When to Use This Calculator vs Others

  • This calculator: Best for bearded dragons, leopard geckos, and turtles to determine insect-to-vegetable ratios.
  • Exotic Pet Nutrition: Use for mammals like ferrets and hedgehogs—different metabolic needs.
  • Fish Nutrition Calculator: Use for aquarium fish—while cold-blooded like reptiles, feeding differs greatly.
  • Pet Age Calculator: Use for dogs and cats—reptile aging patterns are completely different.

Related tools: Exotic Pet Nutrition for ferrets and hedgehogs, Fish Nutrition Calculator for aquatic pets, and Pet Age Calculator to understand life stages.

Frequently Asked Questions

How is reptile food ratio calculated?

Varies by species and age. Adult bearded dragon: 80% veggies, 20% insects. Juvenile: reverse (80% insects). Leopard geckos: 100% insects always.

How often should I feed my bearded dragon?

Juveniles: 2-3x daily (growing fast). Adults: once daily, mostly salad. Offer insects 3x/week. Remove uneaten insects—they can bite!

Do reptiles need calcium supplements?

Yes! Dust insects with calcium at every feeding. Add vitamin D3 2-3x/week if no UVB lighting. Prevents Metabolic Bone Disease (MBD).