How Much to Feed a 18 lb Dog (8.2 kg)

Quick answer A neutered adult dog of 18 lb (8.2 kg) needs about 541 kcal a day, which is about 150 g of a 3,600 kcal/kg dry food. Weigh your dog monthly and adjust by about 10% if the trend is wrong.

Daily calories and grams for a 18 lb (8.2 kg) dog

Resting energy for 8.2 kg is 338 kcal (70 × 8.2^0.75). Multiply by the factor for the life stage to get the day's energy, then divide by the food's kcal per gram.

Life stage	kcal a day	g at 3,400 kcal/kg	g at 3,600 kcal/kg	g at 3,800 kcal/kg
Neutered adult	541	159	150	142
Intact adult	609	179	169	160
Inactive or prone to weight gain	473	139	131	125
Puppy under 4 months	1,014	298	282	267
Puppy 4 months to adult	676	199	188	178

These are averages from the Merck/WSAVA energy factors. Your dog may need 10 to 20% more or less. Check the energy on your own food's label and use the calculator below.

Meals, treats, water and cost

Two meals a day (neutered adult)	75 g each
Three meals a day	50 g each
Treat allowance (10% of calories)	54 kcal: 18 pieces of 3 kcal, or 1.4 of 38 kcal
Water (about 50 mL per kg)	408 mL (range 327 to 490); call the vet above 816 mL
Dry food as a share of body weight	1.8% a day
Calories per kilogram of body weight	66.3 kcal per kg

Monthly food cost at example prices

Cost = grams a day × 30 ÷ 1,000 × price per kg. The prices are examples; use your own.

Price per kg	3.00	4.00	5.00	6.00
Dry food, 3,600 kcal/kg	13.52	18.03	22.54	27.05

How long a bag lasts

Bag size	2 kg	5 kg	10 kg	15 kg
Days at 150 g a day	13	33	67	100

A sample day for a 18 lb (8.2 kg) dog

One way to lay out a neutered adult's day on a 3,600 kcal/kg dry food, with treats counted inside the total.

Time	What	Amount
Morning	Meal	68 g
During the day	Treats and training rewards (counted)	54 kcal
Evening	Meal	68 g
All day	Fresh water (about 408 mL)	Always available

Meals are smaller than the table above because the treat allowance of 54 kcal is taken out of the day's 541 kcal: 487 kcal of meals is 135 g.

If you feed wet and dry together

Split the calories, not the grams. This uses a wet food of 1,000 kcal/kg and a dry food of 3,600 kcal/kg for a neutered adult needing 541 kcal.

Share of calories from wet food	Wet food	Dry food
25%	135 g	113 g
50%	270 g	75 g
75%	406 g	38 g

Do not add wet food on top of the full dry amount: that doubles the calories it replaces.

How 18 lb compares with nearby weights

Weight	kcal a day (neutered adult)	g of 3,600 kcal/kg food	kcal per kg of body weight
10 lb (4.5 kg)	348	97	76.7
12 lb (5.4 kg)	399	111	73.3
15 lb (6.8 kg)	472	131	69.3
18 lb (8.2 kg)	541	150	66.3
20 lb (9.1 kg)	585	163	64.5
25 lb (11.3 kg)	692	192	61.0
30 lb (13.6 kg)	794	220	58.3

If your 18 lb dog is overweight

Using the rule that each body-condition point above 5 (of 9) is about 10% over ideal weight, here is what a weight-loss plan could look like. The calorie target is 1.0 times resting energy at the goal weight, and the pace is 1 to 2% of body weight a week (AAHA 2014). Your vet should confirm the goal and the plan.

Body condition	Goal weight	kcal a day	g of 3,600 kcal/kg food	Weeks at 2% to 1% a week
6 of 9	7.4 kg (16.4 lb)	315	87	5 to 10
7 of 9	6.8 kg (15.0 lb)	295	82	10 to 19
8 of 9	6.3 kg (13.8 lb)	278	77	13 to 27

Not sure of your dog's score? The Dog Body Condition Score tool shows how to check, and the Dog Weight Loss Calculator works from your own goal weight.

Age and life stage if 18 lb (8.2 kg) is your dog's adult weight

Age charts group dogs by adult size. At 18 lb (8.2 kg) the size group is small, which adds 4 human years for each dog year after the second.

Dog's age	Human years (size chart)	Human years (epigenetic formula)
1 year	15.0	31.0
3 years	28.0	48.6
5 years	36.0	56.8
8 years	48.0	64.3
10 years	56.0	67.8
12 years	64.0	70.8

Why a dog twice as heavy does not eat twice as much

Energy needs rise with body weight to the power 0.75, not in a straight line. Moving from 18 lb to 20 lb is a 11% weight increase but only about 8% more calories. At 18 lb (8.2 kg), the neutered figure is 66.3 kcal per kg of body weight.

What changes your dog's number

Neutering and activity. The table shows a 10 to 30% spread between stages.
The food. A richer food means fewer grams for the same calories.
Treats. They count within the daily total.
Weight trend. Weigh monthly, score body condition and adjust by about 10%.
Health. A pet on a veterinary diet or with a health condition should follow the vet's plan.

Frequently asked questions

How much should a 18 lb (8.2 kg) dog eat a day?

A neutered adult of 18 lb (8.2 kg) needs about 541 kcal a day. On a 3,600 kcal/kg dry food that is about 150 g. Intact and inactive dogs need 609 and 473 kcal.

How many meals a day for a 18 lb dog?

Two meals of about 75 g, or three of about 50 g, using the same 3,600 kcal/kg food. Your vet may suggest a different pattern.

How many treats can a 18 lb dog have?

Treats should stay within about 10% of daily calories, which is 54 kcal: 18 pieces of 3 kcal or 1.4 pieces of 38 kcal. Subtract them from the meals.

My 18 lb dog is overweight. How many calories should it eat to lose weight?

If your dog is at body condition 7 of 9 (about 20% over ideal), a goal weight is about 6.8 kg (15.0 lb). A common weight-loss target is 1.0 times resting energy at the goal weight: about 295 kcal a day, or 82 g of a 3,600 kcal/kg food. At 1 to 2% of body weight a week that takes about 10 to 19 weeks. Your vet should confirm the goal and the plan.

How much water should a 18 lb dog drink?

About 408 mL a day (range 327 to 490 mL). Drinking more than about 816 mL a day is a reason to call your vet.

Other weights

Related guides

How we calculate: RER = 70 × kg^0.75, times the life-stage factor, as set out on Formulas & sources. This page is general information, not veterinary advice; ask your vet about your dog.