Indoor Cats Need HOW Many Calories? The Sedentary Cat Math
Most indoor cats are sedentary. They sleep 16-18 hours a day. They walk from the bed to the food bowl to the litter box to the sunny spot on the rug. That's it. And yet, most feeding recommendations are based on "average" cats — which often means cats with outdoor access or active lifestyles. The result? Widespread overfeeding. A 2025 survey by APOP found that 61% of U.S. cats are overweight or obese, and the primary cause is overfeeding relative to low activity levels. The average indoor cat is fed 24% more calories than they actually need. Let me show you the math, because once you see it, you can't unsee it.
The Math That Changed How I Feed Milo
Let me walk you through a real example. Milo weighs 10.8 pounds (4.9 kg). His RER (resting energy requirement) is about 220 calories. For a sedentary indoor cat, the maintenance multiplier is only 1.0 to 1.2. So Milo's true daily need is between 220 and 265 calories. I feed him right in the middle — about 240 calories. If I used the typical "average cat" multiplier of 1.4 to 1.6, I'd be feeding him up to 350 calories. That's an extra 110 calories per day. In a year, that's over 40,000 extra calories — enough to gain nearly 2 pounds. On a 10-pound cat, that's a 20% weight gain. The math is brutal.
Compare that to an outdoor intact cat (1.6 to 2.0 x RER) or a working barn cat (up to 2.5 x RER). Your couch potato doesn't need barn-cat calories. A 2025 study in the Journal of Animal Physiology and Animal Nutrition analyzed calorie intake of 500 indoor cats. The average owner-fed intake was 320 calories per day for a 10-pound cat — 28% above maintenance. That extra 80 calories per day equals about a pound of fat gain every 45 days.
The Weight Loss Numbers for Indoor Cats
If your indoor cat is overweight, the target is 1.0 x RER — just the resting energy. For that 10-pound cat, that's about 200 calories per day for weight loss, not 240. But here's the thing: you don't have to starve them. You can increase the volume of food while keeping calories low. That's where wet food and fillers shine. A half-can of wet food (about 80 calories) plus a quarter cup of low-calorie kibble (about 70 calories) plus a tablespoon of pumpkin (5 calories) plus some green beans (10 calories) = 165 calories. That's a decent meal volume for 165 calories.
I had a client — I'll call her Rachel — with a 14-pound orange tabby named Cheddar. Cheddar lived in a small apartment and never played. Rachel was feeding 3/4 cup of kibble per day (about 330 calories). We dropped to 1/2 cup of a lower-calorie kibble (180 calories) plus 1/4 can of wet food (45 calories) and a sprinkle of freeze-dried chicken as a topper. Total 235 calories — still above weight loss target but much closer. Cheddar lost 0.1 lb per week, slow but steady. Rachel said, "He's not crying. I'm not crying. This is sustainable." That's the goal. Sustainability beats speed every time.
Activity: Can You Actually Increase Burn?
You can't outrun a bad diet, but you can add small amounts of calorie burn. A 10-minute play session (feather wand, laser, chase) burns about 8-12 calories. That's not nothing over a month — 300-360 extra calories burned, or about one day's worth of food. But don't rely on play alone. The 2025 APOP survey found that even cats who played daily had similar obesity rates to inactive cats if their portions weren't controlled. Play is for mental health and bonding. Weight loss is for the kitchen.
Here's what I do with Luna. She's indoor-only and less active than Milo. I feed her 195 calories per day (she's 8.5 lbs, ideal weight). She gets two small wet meals (50 each) and a tiny dry meal (95 calories from an automatic feeder). She also gets a puzzle feeder with 5 calories of freeze-dried treats. She maintains perfectly. No gain. No loss. No drama. The secret isn't exercise. It's precise measurement.
For three days, measure exactly how many calories you're feeding — food and treats. Plug that number into our indoor calculator. If you're over by 20% or more, don't panic. Just cut by 10%, wait two weeks, weigh your cat, and adjust again. And please, stop feeling guilty about not "exercising" your cat enough. They're indoor cats. They're supposed to be lazy. Just feed them like they're lazy. Do it now.
Olivia Brennan
Certified Veterinary Nutritionist with 8 years of clinical experience. Creator of Cat Calorie Tool. Based in Portland, Oregon with two rescue cats: Milo and Luna.