How to balance a BARF ration: a worked example, step by step

A BARF ration is calculated as a percentage of body weight, commonly 2% to 3% of live weight per day in an adult dog, split between muscle meat, raw meaty bone, organ and sometimes vegetables. These benchmarks set a quantity, not a complete profile: balance requires a formulation and supplements (NRC 2006; FEDIAF 2025). This guide walks through the calculation with a worked example, then shows where the figures stop and formulation begins.

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General documentary information. For an individual animal, a veterinarian's advice takes precedence over any online content.

Last updated: 2026-06-15

On this page (balance BARF)

• How do I calculate the daily amount?
• What split between meat, bone, organ and vegetables?
• A worked example for a 20 kg adult dog
• How do I balance calcium and the Ca/P ratio?
• What bone share avoids constipation?
• How do I adjust for a puppy, a working dog or a neutered dog?
• Should I rotate meat sources, and how often?
• Putting it together: from quantity to balance

How do I calculate the daily amount?

The common method expresses the daily amount as a percentage of body weight: about 2% to 3% for an adult dog under raw-feeding community models. A 20 kg dog therefore receives roughly 400 g to 600 g per day. The exact percentage depends on activity, age and body condition.

This calculation sets an amount, not a balance. No body such as FEDIAF or the NRC defines a BARF ration by a simple percentage; they publish nutrient profiles, for protein, calcium and vitamins, to reach. A ration set by live weight can be right in volume yet short on calcium, zinc or iodine (Stockman and Larsen, UC Davis 2013). The percentage also shifts with metabolism: a neutered, sedentary or overweight dog drops towards 2%, a working dog rises towards 3% or more. The NRC in fact reasons in energy needs (kilocalories), more precise than a percentage of weight, and tracking weight and body-condition score over a few weeks is the only reliable judge.

What split between meat, bone, organ and vegetables?

The classic BARF model splits the ration into about 70% muscle meat, 10% raw meaty bone, with the rest in organ, vegetables and supplements. The prey model raw uses an 80/10/10 split: 80% meat, 10% raw meaty bone, 10% organ of which half is liver, with no plant matter. Neither split guarantees nutrient balance.

The term BARF was coined by the veterinarian Ian Billinghurst in 1991, and each component plays a structuring role. Raw meaty bone supplies most of the calcium, organ supplies fat-soluble vitamins, and liver, held near 5% of the ration in the prey model, concentrates vitamin A. Imbalance is quickly costly: too much liver causes a vitamin A excess, too little bone a calcium shortfall. Yet these splits are practical frameworks from raw-feeding communities, not profiles validated by FEDIAF or the NRC. An 80/10/10 ration can honour the proportions while staying short on zinc, iodine, vitamin D or omega-3 (UC Davis, 2013), which is why targeted supplements remain necessary.

A worked example for a 20 kg adult dog

A 20 kg moderately active adult dog fed at 2.5% of live weight receives about 500 g of food per day. Applied to the 80/10/10 prey model, that breaks down to roughly 400 g muscle meat, 50 g raw meaty bone and 50 g organ, of which about 25 g liver. The figures set quantity; balance still needs checking.

The breakdown illustrates how a split converts into grams, and where the watch points sit. The 50 g of raw meaty bone is the ration's main calcium source; the 25 g of liver concentrates vitamin A and should not be exceeded. Even followed to the gram, this bowl can fall short on iodine, vitamin D, vitamin E or long-chain omega-3, because muscle meat and organ do not reliably supply them. The example therefore shows the limit of the percentage method: it answers "how much" but not "is it complete". Oily fish once or twice a week and a quantified mineral and vitamin supplement, set within a formulation, close the gaps the proportions leave open.

The same 500 g can also be read against energy rather than weight, which is the more precise route. The NRC (2006) frames maintenance needs in kilocalories, so a 20 kg adult at rest sits in a different place from the same dog in heavy work, even though both might start from a 2.5% estimate. Two dogs of equal weight can differ by about 30% in energy need depending on activity and neutering, which means the gram figure is a starting hypothesis to confirm, not a result. Tracking body-condition score over three to four weeks, then nudging the amount by about 10% either way, turns the worked example into a ration that fits the individual animal.

How do I balance calcium and the Ca/P ratio?

Calcium balance rests on a sufficient calcium supply and a sound calcium-to-phosphorus ratio, ideally between 1:1 and 2:1 (FEDIAF, 2025). The NRC (2006) sets the adult recommended supply around 1 g of calcium per 1,000 kcal. Raw meaty bone, bone meal or eggshell powder are the usual sources.

Meat is rich in phosphorus but poor in calcium, so a ration without bone or supplement is almost always deficient and unbalanced. Raw meaty bone supplies the calcium in the BARF model; where bone is removed, a teaspoon of eggshell powder, about 5 g, provides on the order of 2,000 mg of calcium but almost no phosphorus, while bone meal supplies both in a ratio close to natural bone. Eggshell powder therefore corrects a phosphorus-heavy ration well, whereas bone meal suits a ration already low in phosphorus. The sensitive case is the growing large-breed puppy, where both excess and shortfall of calcium harm the skeleton: the need tightens, on the order of 2 g to 4.5 g per 1,000 kcal under the NRC, and calls for strict veterinary formulation rather than improvisation.

What bone share avoids constipation?

Raw-feeding models place raw meaty bone around 10% of the ration. An excess hardens stools and can cause constipation, even obstruction; a shortfall causes a calcium deficiency. The bone share is therefore a balance dial between transit and mineral supply, read partly through stool appearance.

Below about 10%, calcium supply falls and stools may loosen; above about 15%, transit hardens and stools turn white and crumbly, a sign of calcium excess that can lead to constipation or obstruction (WSAVA). Stool appearance becomes a practical indicator for adjusting the proportion. Two safety rules frame the choice of bone: cooked bones must be banned, as they splinter into sharp fragments and risk perforation (WSAVA), and weight-bearing bones from large animals can fracture teeth, which number 42 in the adult dog and 30 in the cat. Bone size must match the frame, and the animal supervised while eating, since the dental benefit does not offset a surgical emergency.

How do I adjust for a puppy, a working dog or a neutered dog?

Adjustment runs through energy needs, not the body-weight percentage alone. A growing puppy gets 5% to 10% of live weight by age; a neutered dog sees needs drop by about 20% to 30% and moves towards 2%; a working dog rises towards 3% or more. Weight and body-condition score judge the result.

A puppy ration is best calculated on expected adult weight rather than today's weight, which smooths the need and avoids energy spikes, with the rate reaching the adult 2% to 3% around 12 months (later in large breeds). The puppy also demands a tighter calcium-to-phosphorus framing, especially in large breeds. For the adult, neutering reduces resting energy expenditure while raising appetite, so an unadjusted bowl leads to rapid weight gain; a working or endurance dog spends more and may need a higher fat share. In every case the percentage is only a starting point: reliable tuning tracks weight and body-condition score over three to four weeks, then adjusts the amount by about 10% up or down.

Should I rotate meat sources, and how often?

Rotating meat sources is recommended, because no single protein covers every amino acid and trace element. Alternating several meats across the week lowers the risk of both deficiency and excess. Variety does not, however, replace a formulation, which alone guarantees that needs are met.

Each meat has a distinct profile: beef, poultry, fish and pork differ in fatty acids, iron, zinc and iodine, so a single-source ration risks imbalance. Weekly rotation smooths these gaps and moves the ration closer to FEDIAF profiles (2025) without reaching them automatically. Oily fish plays a particular role, supplying long-chain omega-3 (EPA, DHA) scarce in land meat, and is often served once or twice a week. A watch point applies here: some raw fish contains thiaminase, which degrades vitamin B1, so an excess of raw fish can trigger a thiamine deficiency, hence a measured frequency. Rotation lowers the risk of a one-off deficiency but does not guarantee completeness, since a varied ration can still be short on vitamin D, calcium or iodine (UC Davis, 2013).

Putting it together: from quantity to balance

The percentage method answers one question reliably, how much to feed, and leaves the harder one open, whether the bowl is complete. The worked example for a 20 kg dog shows the gap clearly: a ration correct in grams and proportions can still miss calcium balance, iodine, vitamin D or omega-3. The split models (Billinghurst, 80/10/10) and the live-weight percentages are useful starting frameworks, not validated profiles.

The reliable route combines three steps: set the daily amount from body weight and adjust it to energy needs; secure the calcium supply and the 1:1 to 2:1 calcium-to-phosphorus ratio with bone, bone meal or eggshell powder; then have a veterinary nutritionist formulate the supplements and verify the profile against FEDIAF (2025) or NRC (2006). Petipedia presents these formulas as quantity benchmarks, recalling that they do not replace a veterinary formulation covering nutrient needs.

Related reading (balance BARF)

• How do I calculate a BARF ration for my dog?
• How do I balance calcium in a raw or home-cooked ration?
• What share of raw meaty bone avoids constipation on a BARF diet?
• Glossary: BARF, calcium/phosphorus (Ca/P)
• Hub: Raw, BARF and home-cooked diets

Sources: NRC, Nutrient Requirements of Dogs and Cats 2006; FEDIAF, Nutritional Guidelines 2025; Stockman and Larsen, UC Davis 2013; Billinghurst, Give Your Dog a Bone 1993; WSAVA, raw diets statement; prey model raw and BARF frameworks.