How do I know when to size up prey?

Size up when the snake leaves no visible lump after eating. If the prey is digested within 24 hours with no visible bulge, it's too small. The ideal prey leaves a slight, visible lump that digests within 2-3 days.

My snake won't eat — what should I do?

First check husbandry: is the hot side 88-92°F? Is there a secure hide? Is the snake in shed? Many snakes (especially ball pythons) fast seasonally. If temperatures are correct and the snake is healthy, wait a week and try again. Fasts of 1-3 months are not uncommon.

Frozen-thawed vs. live prey?

Frozen-thawed is strongly recommended. Live prey can bite and seriously injure or kill snakes. F/T prey is also more convenient, cheaper in bulk, eliminates parasite risk, and is considered more humane. Thaw in warm water and ensure it's warm before offering.

How often should an adult ball python eat?

Adult ball pythons should eat every 14-21 days. A 1,500g adult should eat a small rat (70-100g) every two to three weeks. Ball pythons are prone to obesity, so resist the urge to feed weekly once they're full-grown.

Can snakes be overfed?

Yes. Obesity is a serious health problem in captive snakes, causing fatty liver disease, shortened lifespan, and breeding difficulties. An obese snake has a round cross section, visible fat rolls near the tail, and soft, pliable body feel. Reduce feeding frequency if overweight.

Do snakes need vitamins or supplements?

Whole prey (mice and rats) provides complete nutrition — no supplements are needed for snakes fed appropriate whole prey. Vitamin supplementation is only necessary in rare cases where a snake is on a non-traditional diet prescribed by a veterinarian.

Snake Feeding Schedule Calculator

Calculate feeding frequency and prey size for your snake. Based on species, age, and body weight — 10-15% of body weight for juveniles, 5-10% for adults.

Snake Weight

Age Category

Species

Prey Weight Range

80–96 g

12.0% of body weight

Suggested Prey Type

Small rat

range: Small rat to Small rat

Feeding Frequency

Every 9 days

range: every 7–10 days

Yearly Feedings

43 times

at average frequency

Prey Size Guide

Prey Type	Weight	Suitable For
Pinky Mouse	0.5-2 g	Tiny hatchlings only
Fuzzy Mouse	3-7 g	Hatchling/small juvenile
Hopper Mouse	8-15 g	Young juvenile
Adult Mouse	20-35 g	Juvenile/small adult
Weaned Rat	35-60 g	Juvenile/small adult
Small Rat	60-100 g	Adult snake
Medium Rat	100-180 g	Large adult snake
Large Rat	180-300 g	Very large snake
Rabbit	300+ g	Large pythons, large rat snakes

Obesity Risk: Low

Standard feeding schedule

Health Monitoring Checklist

Metric	Healthy	Warning Sign
Body Shape	Slightly rounded, not bulging	Obese (fat rolls), or angular (underfed)
Feeding Response	Strikes and eats within minutes	Refuses food for weeks (check temps)
Digestion Time	48-72 hours for small prey	Bulge visible after 5+ days
Growth Rate	Steady size increases	No growth for 6+ months
Shedding	Clean one-piece sheds monthly	Stuck shed or excessive shedding

Best Feeding Practices

Frozen-thawed prey is SAFER than live	Live prey can bite and injure snakes seriously
Don't handle snake for 48 hours post-feeding	Prevents regurgitation; risk of serious damage
Feed in a separate container	Prevents accidental substrate ingestion and stress
Weigh both snake and prey on a gram scale	Precision prevents overfeeding and obesity
Keep feeding records	Track growth, feeding response, and health trends

Pro Tips

Always use frozen-thawed prey — safer and more humane than live.
Thaw prey in warm water and ensure it\u0027s warm before offering.
Use a separate feeding enclosure if possible — reduces stress and substrate ingestion.
If the snake refuses food, check temps first (snakes won\u0027t eat if too cold).
Recalculate feeding size as your snake grows — update this tool monthly.

Planning notes, formulas, and examples

About the Snake Feeding Schedule Calculator

Snakes require appropriately sized prey at species-specific intervals for optimal health. The general guideline is to feed prey that is 10-15% of the snake's body weight for juveniles and 5-10% for adults. Feeding frequency varies from every 5-7 days for actively growing babies to every 14-21 days for large adult snakes.

Prey size should be approximately 1-1.5× the width of the snake at its widest point. Overfeeding leads to obesity (a serious health concern in captive snakes), while underfeeding causes growth stunting and nutritional deficiency. The prey-to-body-weight ratio provides a more precise measurement than visual width matching.

This calculator estimates the correct prey weight, prey type (mouse, rat, or other), and feeding frequency based on your snake's species, weight, and age. It also provides guidance on when to size up prey and how to adjust feeding during seasonal slowdowns.

When This Page Helps

Improper feeding is one of the most common issues in snake husbandry. Too-large prey causes regurgitation; too-small prey causes malnutrition. Feeding too often leads to obesity, while feeding too rarely stunts growth. It gives precise, weight-based recommendations.

How to Use the Inputs

Weigh your snake in grams (use a kitchen scale).
Select the age category: hatchling, juvenile, sub-adult, or adult.
Select the species type for metabolism rate adjustment.
Review the recommended prey weight in grams.
Match the prey weight to available feeder sizes.
Adjust feeding frequency based on the schedule shown.

Formula used

Prey Weight:
Hatchling: Body Weight × 10-15%
Juvenile: Body Weight × 10-12%
Sub-adult: Body Weight × 7-10%
Adult: Body Weight × 5-7%

Feeding Frequency:
Hatchling: every 5-7 days
Juvenile: every 7-10 days
Sub-adult: every 10-14 days
Adult: every 14-21 days

Example Calculation

Result: 80-96g prey every 7-10 days (small adult mouse or weaned rat)

An 800g juvenile snake: Prey = 800 × 10-12% = 80-96 grams. This corresponds to a small adult mouse (~30g × 3) or a single weaned rat (~60-90g). Fed every 7-10 days, this provides steady growth without obesity risk. Weigh the snake monthly to track growth rate.

Tips & Best Practices

Always weigh your snake and prey on a gram scale for precision.
Feed frozen-thawed prey — it's safer for the snake and more humane.
Don't handle your snake for 48 hours after feeding to prevent regurgitation.
If the snake refuses food for 2+ weeks (non-breeding season), check temperatures first.
A slight visible lump after eating is normal; a large bulge means prey is too big.
Keep feeding records — note date, prey type, weight, and whether the snake accepted.

Prey Size Reference Chart

Common feeder sizes and approximate weights: Pinky mouse 2-3g, Fuzzy mouse 5-8g, Hopper mouse 10-15g, Adult mouse 25-35g, Rat pup 10-20g, Weaned rat 40-60g, Small rat 70-100g, Medium rat 120-180g, Large rat 200-300g, Jumbo rat 350-500g. Match your snake's percentage-based prey weight to the closest feeder size.

Understanding Snake Metabolism

Snakes have incredibly slow metabolisms compared to mammals. They can survive weeks to months without food, and their digestive process takes 3-7 days per meal. This is why feeding frequency is measured in weeks, not days. Overfeeding in frequency (even with correctly sized prey) causes obesity because the snake doesn't need the caloric intake.

Seasonal Feeding Adjustments

Many temperate and sub-tropical snakes naturally reduce or refuse food in winter months. Ball pythons commonly fast from November through March. This is normal behavior driven by hormonal cycles. Don't force-feed during seasonal fasts unless the snake loses more than 10% body weight — they are designed to handle these periods.

Sources & Methodology

Last updated: February 10, 2026

Frequently Asked Questions

Size up when the snake leaves no visible lump after eating. If the prey is digested within 24 hours with no visible bulge, it's too small. The ideal prey leaves a slight, visible lump that digests within 2-3 days.