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Pet Calorie Calculator

Estimate daily calories for a dog or cat using the vet RER formula. Adjust for life stage, activity, neuter status, and weight goal.

Quick presets

Species

kg

Enter your pet's actual current weight, not an ideal target.

Most adult pet dogs and cats

Activity level

Weight goal

Food serving estimate

Pick the closest food profile or read the kcal/cup figure off your actual bag. The cups number adjusts automatically.

Typical 800 kcal/day

Cup volumes are based on an 8 oz (237 mL) US measuring cup of dry food at the kcal density shown. A standard 350kcal/cup is common for mainstream adult dry kibble; check your bag's feeding guide for the exact figure.

Life-stage factors for dogs

3 x RER

Puppy under 4 months

Rapidly growing puppies need about 3 x RER. Feed measured meals 3 to 4 times per day.

2 x RER

Puppy 4 months to adult size

Older puppies are usually fed at about 2 x RER until they reach their adult body weight.

1.60 to 1.80 x RER

Adult, intact

Intact adults usually need slightly more food than neutered adults at the same weight.

1.40 to 1.60 x RER

Adult, neutered or spayed

Neutering lowers maintenance energy. Watch for weight gain in the first 6 to 12 months after surgery.

1.20 to 1.40 x RER

Adult, prone to weight gain

Use the lower end of the maintenance range and re-weigh every 2 weeks. See the weight-loss option for active reduction.

1.20 to 1.40 x RER

Senior

Senior pets generally need less energy. Adjust for health conditions, joint disease, and dental status with your vet.

1.60 to 2 x RER

Pregnant (last 3 weeks)

Pregnancy energy needs rise sharply in the last third. Feed a growth or all-life-stages diet, not a maintenance diet.

2 to 6 x RER

Lactating

Lactation energy needs depend on the number of nursing offspring and the week of lactation. Feed to appetite under veterinary guidance.

Factors are taken from the AAHA / WSAVA feeding guidelines and Hand et al., Small Animal Clinical Nutrition. Use them as planning ranges, not as exact medical targets.

Important

This calculator gives a maintenance estimate based on the published veterinary RER equation and standard life-stage factors. It is not a medical recommendation. Energy needs vary with breed, climate, health, and individual metabolism. For pets that are unwell, very young, very old, pregnant, or being treated for a medical condition, follow your veterinarian's specific feeding plan.

How to use

  1. Pick Dog or Cat. The life-stage list and activity options update to match the species.
  2. Enter your pet's current weight and pick kg or lb. Use Switch units to convert without retyping.
  3. Choose the life stage that best matches your pet today: adult neutered for most pet dogs and cats, puppy or kitten for growing animals, senior for older pets, or pregnant or lactating where applicable.
  4. Pick an activity level. Indoor low-activity cats and dogs sit at the bottom; sled, herding, hunting, and service dogs are at the very-active end.
  5. Optionally switch the weight goal to Lose (0.8x) or Gain (1.2x) for adult pets that need a steady change in body condition.
  6. Read the kcal-per-day range, RER baseline, and approximate cups per day on your chosen food. Click Copy summary to save a plain-text snapshot for your vet visit or feeding log.

About this tool

Pet Calorie Calculator estimates the daily energy your dog or cat needs using the same equation veterinarians and pet food companies use: Resting Energy Requirement (RER) equals 70 multiplied by body weight in kilograms raised to the 0.75 power, then multiplied by a life-stage and activity factor to get the Daily Energy Requirement (DER). Enter your pet's species, current weight in kilograms or pounds, life stage (puppy under 4 months, puppy 4 months to adult, kitten, adult intact, adult neutered, adult prone to weight gain, senior, pregnant, or lactating), activity level (couch potato through very active working dog), and weight goal (maintain, lose, or gain). The tool reports the RER baseline, the life-stage factor range applied, the activity adjustment, an optional 0.8x weight-loss or 1.2x weight-gain multiplier on top of maintenance, and the final DER as a kcal-per-day range so you can budget within a sensible band rather than chasing a single brittle number. Approximate daily cup counts are shown for three common dry-food kcal densities (280, 350, and 450 kcal per 8-ounce cup), with a clear note to confirm the figure on your actual bag's feeding guide. Life-stage factor ranges follow the published feeding guidelines from the American Animal Hospital Association (AAHA), the World Small Animal Veterinary Association (WSAVA), and Hand et al.'s Small Animal Clinical Nutrition. Common scenario presets cover small, medium, and large adult dogs, puppies, indoor cats, active cats, and kittens so you can compare your pet to a baseline at a glance. The number is a planning estimate; pets that are unwell, growing rapidly, pregnant, lactating, or being treated for a medical condition need a veterinarian-supervised feeding plan. Everything runs in your browser; weight and life-stage inputs are never uploaded to a server.

Free to use. Works in your browser. No signup, no login.

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