Key Takeaway
The ultimate frozen rat size chart. Stop guessing and use our accurate weight-based chart to find the perfect feeder for your reptile.
Table of Contents
When transitioning your snake from mice to rats, the terminology can be incredibly confusing. What exactly is a "Weanling"? Is a "Pup" bigger than a "Fuzzy"?
To ensure you are feeding the correct 10-15% of your snake's body weight, you need an exact gram-to-gram breakdown (see our what size mouse for Ball Python guide for snake-to-prey weight ratios). Here is the definitive Frozen Rat Size Chart.
The Master Frozen Rat Size Chart (Referenced in our Ball Python feeding guide)
Note: Weights can vary slightly depending on the breeder, but these are the industry standard classifications used by Loxahatchee Rodents and other premium suppliers.
| Rat Classification | Weight Range (Grams) | Age Equivalent | Best For... |
|---|---|---|---|
| Pinky Rat | 5g – 12g | 1 – 4 Days Old | Hatchling colubrids, Hatchling Ball Pythons |
| Fuzzy Rat | 13g – 19g | 5 – 13 Days Old | Young juvenile Ball Pythons, Adult Corn Snakes |
| Rat Pup | 20g – 29g | 14 – 20 Days Old | Sub-adult Kingsnakes, Juvenile Ball Pythons |
| Weaned Rat (Weanling) | 30g – 45g | 3 – 4 Weeks Old | Small adult Pythons, Sub-adult Boas |
| Small Rat | 46g – 79g | 5 – 6 Weeks Old | Adult Male Ball Pythons, Sub-adult Boas |
| Medium Rat | 80g – 149g | Young Adult | Adult Female Ball Pythons, Adult Boas |
| Large Rat | 150g – 249g | Mature Adult | Large Boas, Small Reticulated Pythons |
| Jumbo Rat | 250g – 350g+ | Retired Breeder | Large Constrictors, Monitor Lizards |
Why Switch from Mice to Rats?
If you own a heavy-bodied snake like a Python or Boa, transitioning to rats is non-negotiable.
- Protein to Fat Ratio: Rats naturally possess a higher protein and fat content than adult mice, providing better nutrition for heavy-bodied growth.
- Digestive Ease: Feeding one Medium Rat (100g) is biologically easier on a snake's digestive tract than feeding four Adult Mice (25g each) in a single sitting.
(Note: If you keep slim-bodied colubrids, rats are generally not recommended due to their high fat density. See our dedicated Corn Snake Frozen Mouse Size Chart for specialized colubrid guidelines).
How to Weigh Your Feeders
Never eyeball prey sizes. Buy a digital kitchen scale that measures in grams. Weigh your snake, calculate 10-15% of that weight, and reference the chart above to order the precise classification of frozen rat required (visit our guide on where to buy frozen mice and rats for top-tier sources).
