Sedentary (little to no exercise)
Lightly Active (regular walks/play)
Moderately Active (daily vigorous play)
Very Active (high energy, hunts)
Extremely Active (working cat, very high energy)
Healthy
Weight Loss
Weight Gain
Other (consult vet)
Your Cat's Estimated Daily Kcal Needs:
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Kcal
Understanding Your Cat's Daily Calorie Needs
Determining the right amount of food for your feline friend is crucial for their health and well-being.
Cats, unlike dogs, have specific nutritional requirements and metabolic rates that influence their energy needs.
This calculator provides an estimated daily caloric intake based on several key factors.
The Math Behind the Calculation
The calculation is based on the Resting Energy Requirement (RER) and then adjusted for the cat's specific lifestyle and condition.
Calculate Resting Energy Requirement (RER):
This is the energy a cat needs at rest. The formula used is:
RER (kcal/day) = (Body Weight in kg ^ 0.75) * 70
Where '^ 0.75' denotes raising the weight to the power of 0.75.
Calculate Daily Energy Requirement (DER):
The RER is then multiplied by a factor that accounts for the cat's activity level, life stage, and health condition. This is known as the Daily Energy Requirement (DER).
DER (kcal/day) = RER * Activity Factor * Life Stage Factor * Health Condition Factor
The factors used in this calculator are common veterinary guidelines:
Activity Level: Sedentary (1.2), Lightly Active (1.375), Moderately Active (1.55), Very Active (1.725), Extremely Active (1.9).
Life Stage: Kittens require more calories for growth (approx. 1.2x RER), while adults, seniors, and neutered/spayed cats typically need maintenance levels (approx. 1.0x RER).
Health Condition: Cats needing to lose weight require fewer calories (approx. 0.8x RER), while those needing to gain weight require more (approx. 1.2x RER). Healthy cats are at maintenance (approx. 1.0x RER).
How to Use the Calculator
To get an accurate estimate, you will need to know:
Your cat's current weight in kilograms.
Your cat's general activity level.
Your cat's current life stage (kitten, adult, senior, neutered/spayed).
Any specific health conditions that might affect their caloric needs (e.g., weight loss or gain goals).
Enter these details into the calculator, and it will provide a recommended daily calorie intake.
Important Considerations
This calculator provides an estimate. Every cat is an individual, and their metabolism can vary.
Always consult your veterinarian for personalized dietary recommendations, especially if your cat has underlying health issues or if you are unsure about their nutritional needs.
The calorie content of different cat foods also varies significantly, so always check the packaging of your chosen food and adjust portion sizes accordingly.
function calculateKcal() {
var catWeightKg = parseFloat(document.getElementById("catWeightKg").value);
var activityLevel = parseFloat(document.getElementById("activityLevel").value);
var lifeStage = parseFloat(document.getElementById("lifeStage").value);
var healthCondition = parseFloat(document.getElementById("healthCondition").value);
var resultDiv = document.getElementById("result");
var resultValueDiv = document.getElementById("result-value");
var resultUnitDiv = document.getElementById("result-unit");
if (isNaN(catWeightKg) || catWeightKg <= 0) {
resultValueDiv.textContent = "Invalid";
resultUnitDiv.textContent = "Input";
resultDiv.style.borderColor = "#dc3545";
return;
}
// Calculate RER (Resting Energy Requirement)
var rer = Math.pow(catWeightKg, 0.75) * 70;
// Calculate DER (Daily Energy Requirement)
var der = rer * activityLevel * lifeStage * healthCondition;
// Round to nearest whole number for practical use
var finalKcal = Math.round(der);
resultValueDiv.textContent = finalKcal;
resultUnitDiv.textContent = "Kcal";
resultDiv.style.borderColor = "#28a745"; // Success green
}