Kitten Feeding Calculator
How much to feed a kitten each day.
Starting estimate from published formulas. Your vet knows your pet.
How to use the kitten feeding calculator
- Enter the kitten's weight now. A kitchen scale in grams is easier than guessing pounds for a small kitten.
- Enter age in weeks. Age does not change the 2.5 factor. It changes the countdown to an adult diet.
- Leave free choice selected unless you already split the day into meals. Merck allows both.
- If you choose meals, set how many. That only divides the calorie day.
- Replace kcal per can. 75 is an example. The can count is useless until the label replaces it.
One factor for the whole growth period
Merck's nutrition table gives kittens a single multiplier: 2.5 × resting energy. It does not step down at 4 months the way the puppy table does. The page opens at 2.2 lb and 10, and the day is 175 kcal at a factor of 2.5 × RER.
Cans, if the example 75 kcal were your can, come out as 2.25. Swap the example before you open a tin. There is no cup control on this page. If you feed dry food, divide the calorie day by the kcal per cup on that bag yourself, or use the cat food page once the kitten is on an adult factor.
A kitten may need as much as 30% more or less than the calculated day. Weekly weight tells you which side you are on.
Free choice is a real option in the manual
Merck's nutrition chapter says kittens may be fed free choice. The feeding-practices chapter says growing kittens, and pregnant or nursing queens, can be fed free choice or several times a day. The opening setting is free choice, so the meal line reads as food left available rather than a bowl count.
Switch to meals and the same 175 kcal is divided by the number you type. The page does not claim three meals is required. Three is only the number in the box if you turn meals on, because the control needs a starting split.
Free choice is not a licence to ignore the scale. A kitten that is racing ahead of the wide weight band on the kitten weight page may be eating past the day this formula suggests. That is a reason to measure, not a reason to panic from one reading.
When the adult diet starts
Merck says kittens are generally moved to an adult diet sometime between 8 and 12 months. The opening age is 10 weeks, so the countdown to the start of that window is 5.7. Inside the window, the kitten feeding factor is still 2.5 until you actually change the food. This page does not flip to the adult 1.2 by itself.
Birth weight and weekly gain live on the weight page. They are not used to shrink or grow this bowl. A light kitten and a heavy kitten of the same age get calories from the weight you type, not from a target weight.
Queen's milk, orphan feeding and bottle volumes are not calculated. Those are clinic and rescue problems with their own charts. If the kitten is still nursing or still on a bottle, do not treat this can line as the whole diet.
Kitten calories by weight at 10 weeks
| Weight | kcal per day | Cans per day | Months until adult-diet window |
|---|---|---|---|
| 1 lb | 95 kcal | 1.25 | 5.7 |
| 2.2 lb | 175 kcal | 2.25 | 5.7 |
| 4 lb | 275 kcal | 3.75 | 5.7 |
10 weeks old, kitten factor 2.5, 75 kcal per can (an example). The adult-diet window Merck gives opens at 8 months.
Tips and common mistakes
- Use a growth food until the 8–12 month window, not an adult maintenance food in a smaller can.
- Free choice still needs a scale. Leaving food out does not mean ignoring how fast the kitten gains.
- Do not copy a puppy's 'under 4 months times 3' factor onto a kitten. The kitten row is 2.5.
When to call your vet
- The kitten is not gaining, or is losing, especially under 8 weeks.
- Vomiting, diarrhoea, or a sudden stop in nursing or eating.
- You are bottle-raising an orphan and you need volumes, not a can of growth food.
- You want to switch to adult food well before 8 months because the kitten looks big.
Frequently asked questions
How much should a kitten eat?
At 2.2 lb the day is 175 kcal, which is 2.5 × resting energy. The example can turns that into 2.25. Your label replaces 75 kcal before the can count means anything.
Should kittens be fed free choice?
Merck says they may. The feeding chapter also allows several meals a day. This page opens on free choice. Meals are there if you already portion the day. Neither setting changes the calorie total.
When do kittens switch to adult food?
Sometime between 8 and 12 months, per Merck's feeding chapter. From the opening age the window starts in about 5.7. Stay on the kitten factor until you make that change with your vet.
Does age change the calories?
Not the factor. Age changes the countdown to the adult-diet window. Calories follow weight. A heavier week should show a larger day even if the birthday has not moved.
Is 75 kcal per can a real food?
No. It is an example so the page can show cans. Read your label. Two cans with the same size can differ a lot, and this site does not store brands.