How many calories does my dog need per day?

Use the RER formula: 70 × (body weight in kg)^0.75, then multiply by a life-stage factor. A 30 lb adult dog needs roughly 770–900 kcal/day; a puppy of the same weight needs up to 1,400 kcal/day.

Do neutered dogs need fewer calories?

Yes. Spaying or neutering reduces a dog's resting metabolism by approximately 15–20%. Our calculator applies a 0.85 multiplier for neutered/spayed dogs, matching current AAFCO veterinary guidelines.

Dog Calorie Calculator

Q: What is Body Condition Score (BCS)?

BCS is a 1–9 scale that measures body fat. Score 5 is ideal — you can feel the ribs but not see them. Dogs above 5 need fewer calories; below 5 need more. Ask your vet to assess your dog's BCS.

Find out exactly how many calories your dog needs per day — adjusted for their size, age, activity, and body condition.

Last reviewed: June 2026

Dog's Weight30 lbs

2 lbs180 lbs

Life Stage

Activity Level

Neutered / Spayed?

Body Score5 — Ideal

1 (thin)9 (obese)

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RER = 70 × kg^0.75 · National Research Council (NRC) · AAFCO guidelines

BCS adjustment and neuter multiplier (×0.85) follow current AAFCO-aligned veterinary nutrition practice.

Veterinary note: Results are estimates based on veterinary RER formulas. Individual needs vary — consult your veterinarian before making significant changes to your dog's diet or portion sizes.

How Many Calories Does a Dog Need?

Dog calorie needs are calculated using the Resting Energy Requirement (RER) formula: 70 × (body weight in kg)^0.75. This baseline is then multiplied by factors for life stage, activity level, and whether your dog is spayed or neutered.

Dog Weight	Puppy	Adult (normal)	Senior
10 lbs	660 kcal	365 kcal	320 kcal
20 lbs	1,045 kcal	580 kcal	510 kcal
30 lbs	1,390 kcal	770 kcal	675 kcal
50 lbs	2,020 kcal	1,120 kcal	980 kcal
80 lbs	2,870 kcal	1,595 kcal	1,395 kcal

What is Body Condition Score (BCS)?

BCS is a 1–9 scale that measures how much body fat your dog carries. Score 5 is ideal — you can feel the ribs easily but not see them. Dogs with BCS above 5 need fewer calories to lose weight; those below 5 need more. Ask your vet to assess your dog's BCS at the next checkup.

Neutered Dogs Need Fewer Calories

Spaying and neutering reduces a dog's metabolism by about 15–20%. This is why neutered dogs are more prone to weight gain on the same food. Our calculator applies a 0.85 multiplier for neutered/spayed dogs — matching current veterinary guidelines.