Cat Food Portion Calculator

Last updated: June 2026

Cat weight

Life stage

Food type

Food calories per 100g

kcal

Optional. Use the food label if available.Food price per kg

GBP

Daily calories

238 kcal

Daily food amount

68g

Per meal (2x/day)

34g

Monthly cost

GBP 8

Formula

RER = 70 x weight_kg^0.75. MER = RER x life factor. Daily grams = daily calories / calories per gram.

These are guidelines only. Always check your specific food packaging. Adjust based on body condition. Consult your vet if unsure. Cats should have access to fresh water at all times, especially if fed dry food.

About this calculator

The Cat Food Portion Calculator estimates daily calories, food grams, meal portions, and monthly cost from cat weight, life stage, lifestyle, and food calories. It helps compare dry, wet, and raw food portions while keeping a cautious health-first approach.

Cat food calorie method

The calculator uses metabolic body weight to estimate resting energy requirement, then applies a cat life-stage factor.

RER = 70 x weight_kg^0.75
MER = RER x cat life factor
daily grams = daily kcal / (food kcal per 100g / 100)

How to use the cat food calculator

Enter your cat weight in kilograms.
Choose indoor, active, kitten, senior, weight loss, pregnant, or lactating stage.
Choose dry, wet, or raw food.
Use the calories per 100g from the label if possible.
Review daily grams and per-meal amounts.
Monitor weight and body condition over time.

Worked examples

Indoor neutered cat

Input: 4kg cat, indoor adult, dry food at 350 kcal/100g

Calculation: RER about 198 kcal. MER = 198 x 1.2 = 238 kcal.

Result: About 68g of dry food per day.

Wet food comparison

Input: Same cat, wet food at 85 kcal/100g

Calculation: 238 / 0.85 = 280g.

Result: Wet food portion by weight is much larger because it contains more water.

Dry food and water

Cats fed mostly dry food should always have access to fresh water. Wet food contributes more moisture, but all cats still need clean drinking water available.

Why cat portions vary

Indoor cats, outdoor cats, kittens, seniors, pregnant cats, and cats needing weight loss can have very different energy needs. Body condition and vet guidance matter.

Veterinary nutrition disclaimer

This calculator is for general feeding guidance only and is not veterinary advice. Cats with medical conditions, appetite changes, weight loss, obesity, pregnancy, or lactation should be assessed by a vet.

Frequently asked questions

Why does my cat need fewer calories than I expected?

Cats are small animals and calorie-dense foods add up quickly. Indoor and neutered cats often need less energy than active outdoor cats.

Can I free-feed dry food?

Some cats overeat when free-fed. Measured portions can help with weight control, but feeding style depends on the cat.

Should kittens eat more?

Kittens need more calories per kg than adults because they are growing. Use kitten food and ask your vet for age-specific guidance.

What if my cat is overweight?

Speak to your vet. Cat weight loss should be gradual because rapid weight loss can be dangerous.

How do I use kcal per pouch?

If a pouch gives total kcal, divide your daily target by kcal per pouch to estimate pouches per day.

Related calculators

Cat Age Calculator
Pet Medicine Dose Calculator
Dog Food Portion Calculator

What does this mean?

This calculator is designed to help you understand the likely number before you make a decision or start an application.

Your result should be checked against official UK guidance, especially if your circumstances include dependants, exemptions, prior leave, or a complex immigration history.

Treat the figure as a planning tool rather than legal advice. Where the answer affects an application deadline or major payment, speak to an authorised adviser.