How Much Should a Cat Eat Per Day?
Learn the exact daily food amount for your cat based on weight and life stage. Guide based on veterinary formulas.
How to Determine Your Cat's Daily Food Amount?
Feeding your cat the correct amount of food is crucial for their health. While individual needs vary, most cats have calorie requirements based on their weight and life stage. This guide explains how to calculate your cat's food amount using veterinary formulas.
What is RER (Resting Energy Requirement)?
RER is the amount of calories your cat needs while at rest. It varies based on weight and is calculated using: RER = 70 × (weight in kg ^ 0.75). For example, a 4kg cat has an RER of approximately 200 kcal.
Calculating DER (Daily Energy Requirement)
Based on RER, adjust for life stage and activity level to get DER. Kittens use RER × 2.0–2.5, neutered adult cats use RER × 1.2, and senior cats use RER × 0.7–1.0. Add 20% for high activity or subtract 20% for low activity.
Food Amount by Life Stage
- Kittens (0-1 year): Require maximum nutrition. Three meals per day recommended.
- Adult cats (1-10 years): Maintain stable weight. Two meals per day is typical.
- Senior cats (10+ years): Require easily digestible, high-quality food. Two meals per day recommended.
What to Check When Choosing Cat Food
When selecting food, check the "kcal per 100g" listed on the package. Most dry cat foods contain 350–450 kcal/100g (wet foods are typically 70–120 kcal/100g). Cat food calories are more influenced by fat content than protein, so always check the actual calorie value on the package when adjusting portions.
Feeding Amount Calculation Process
Weight (kg)
↓
RER = 70 × (weight ^ 0.75) kcal
↓
Apply life stage multiplier
(Kitten: ×2.0–2.5, Adult: ×1.2, Senior: ×0.7–1.0)
↓
Activity adjustment (±20%)
↓
DER (Daily Energy Requirement) kcal
↓
Divide by dry food calories (kcal/100g)
↓
Daily recommended food amount (g)Life Stage Calorie & Feeding Examples (4kg cat)
| Life Stage | Multiplier | Calories | Food Amount |
|---|---|---|---|
| Kitten | RER×2.0–2.5 | ~400–500 kcal | ~115–140g |
| Adult (Neutered) | RER×1.2 | ~240 kcal | ~65g |
| Senior/Weight Care | RER×0.7–1.0 | ~140–200 kcal | ~40–55g |
(Food basis: 350 kcal/100g)
Use our free cat weight calculator for precise calculations. Enter your cat's weight, life stage, activity level, and food calories to get personalized feeding amounts.
Sources & References
- Cornell Feline Health Center - Feline Nutrition and Dietary Requirements
- AAFCO (Association of American Feed Control Officials) - Feline Nutrition Standards
- American Veterinary Medical Association - Feline Health Management
- ASPCA - Cat Nutrition and Obesity Prevention
Veterinary Consultation is Important
This guide is for general information and can vary based on individual cat's health status, metabolism, and any conditions. If your cat has obesity, diabetes, or kidney disease, always consult with your veterinarian for customized diet.