About WoofChef

What WoofChef actually does.

WoofChef is a nutrition calculator for homemade dog food.

It estimates the nutrient totals in your recipe using published food data. It then compares those totals with nutrition guidelines published by the National Research Council for healthy adult dogs on maintenance diets.1

Beta testingWoofChef is still being tested. Errors can occur. Re-test your recipes regularly, especially after updates or ingredient changes.

Disclaimer

WoofChef is not veterinary advice

It is a recipe planning tool for healthy adult dogs only. It is not suitable for puppies, pregnant or nursing dogs, or for medical or therapeutic diets.

No veterinarian has formulated or approved any result here for your dog. A recipe that meets NRC standards is not automatically suited for your dog. Always consult a professional before changing your dog's diet.

On this page
01

Foundations

How WoofChef works

What the tool calculates, who it supports, and where Guided formulation fits.

Recipe check

The basic recipe check

When you build a recipe, you choose each ingredient, its raw or cooked state, and the amount you used. WoofChef then uses published food data to estimate the total nutrient content.

Next, it compares the complete recipe with NRC guidelines. The result shows which nutrients meet the NRC values, which may be too low or too high, and which cannot be checked because information is missing.1

Some WoofChef modes can estimate how many calories your dog may need each day. This is a starting point. The best way to learn your dog's actual needs is to track how much they eat and how their weight and body condition change over time.

Supported scope

Who WoofChef is for

WoofChef is for owners of healthy adult dogs who prepare their dog's food at home and want a first-step analysis against an established canine nutrition standard.

It does not account for breed-specific needs, allergies, illness, medication, digestive tolerance, clinical history, or food safety. It cannot model every interaction between foods and nutrients. Zinc and copper are one example: they can affect one another in dogs, but the research does not provide one simple formula that applies to every dog.7

WoofChef is not designed for puppies, pregnant or nursing dogs, or dogs that need a medical or therapeutic diet. A veterinary nutritionist can consider your dog, the recipe, and the wider clinical picture together. WoofChef cannot replace that work.

Find a veterinary nutrition specialist

Can WoofChef generate a new recipe?How Guided formulation fits into the product

Guided mode

Guided can build a starter recipe

Yes. Guided mode can help you build from scratch. You choose a base protein, a base carb or starch, other ingredients to include, foods to avoid, and whether you are open to supplements.

WoofChef tries to build a recipe from those choices that meets NRC targets. Guided will not always find one. When the available foods cannot fill a gap, WoofChef shows what remains missing instead of presenting the recipe as complete.

Guided is a planning tool, not a veterinary prescription.

02

Standard and calculation

The nutrition standard

Why WoofChef uses NRC 2006, how recipe totals are calculated, and why the comparison basis matters.

NRC 2006

What “NRC” means and why WoofChef uses it

The National Research Council, or NRC, was part of the U.S. National Academies, a private nonprofit organization that brings experts together to review scientific evidence. In 2006, an NRC committee published Nutrient Requirements of Dogs and Cats, a comprehensive report on canine and feline nutrient needs.1

AAFCO is the name many Americans recognize from pet food labels. Its Dog Food Nutrient Profiles support “complete and balanced” claims for commercial foods. Their revision considered NRC 2006 alongside other research and practical experience.2

WoofChef is not evaluating a commercial food label. It compares a home-prepared recipe with published requirements for a healthy adult dog. NRC adult-maintenance values are the more appropriate reference for that purpose.

Recipe math

How WoofChef calculates a recipe

Food data reports nutrient values per 100 grams. WoofChef adjusts those values to the amount you entered, then adds the foods together to calculate the complete recipe.

For calories, WoofChef normally uses the accepted energy value published for each food. Modified Atwater remains only for compatible older records with a complete set of crude fiber, ash, moisture, protein, and fat. Total dietary fiber is not substituted for crude fiber, and carbohydrate by difference is not substituted for NFE.6

The page may show Est. carbs, calculated as accepted carbohydrate by difference minus accepted total dietary fiber. It is a gram estimate, not NFE, digestible carbohydrate, or a calorie input. The optional calorie split is separate and is withheld when its data or arithmetic is incomplete.3

WoofChef applies the selected NRC basis, relevant adult-maintenance lower bounds, targets, relationships, and upper limits. Analysis Mode, Guided, saved results, and printable reports use the same final analysis.

Comparison basis

Two ways to compare a recipe with NRC

WoofChef supports two expressions of NRC 2006 adult-dog values. They answer related but different questions.1

Every result names its basis: NRC per 1,000 kcal or NRC metabolic weight. The two expressions are not stacked as separate verdicts.

Per 1,000 kcal

Nutrient concentration by energy

This asks how much of each nutrient the recipe supplies for every 1,000 kilocalories. Analysis Mode offers it for recipe-level inspection.

Metabolic weight

Daily needs for a particular dog

This calculates a daily requirement from body weight raised to the 0.75 power. Guided uses metabolic weight; Analysis Mode also offers it.
03

Interpretation

How to read your result

The lower NRC bound, the recommended target, and what each result does or does not establish.

Result states

What each result means

Every label describes what the calculation found on the named NRC basis. It is never a basis-free green light.

Minimum

The lower bound is MR or AI

WoofChef uses Minimum Requirement where NRC publishes one, otherwise Adequate Intake. Falling below an AI means adequacy is not established; it is not a demonstrated deficiency threshold.

Target

The target is RA

Recommended Allowance is the higher target. A recipe can reach every lower bound while remaining below one or more RAs.

Meets NRC Targets

Every applicable RA is reached and no problem was found in checked hard limits. This is still a calculation, not veterinary approval.

Meets NRC Minimums

Every applicable MR or AI is reached. Some nutrients may remain below RA. This does not mean the recipe is ideal for your dog.

Gaps, excesses, or notes

One or more nutrients may be too low, too high, or out of balance. Open the details to see what needs review.

Cannot verify

WoofChef cannot prove part of the required nutrition or safety check. The result explains what the uncertainty affects.

Do not feed as-is

The recipe crosses a safety limit WoofChef checks. Do not feed it as entered. Review and change it first.

04

Evidence and uncertainty

Food data and uncertainty

Where the numbers come from, how WoofChef preserves their meaning, and what happens when a value is missing.

Source data

Where the food numbers come from

WoofChef uses representative food-composition data. Its primary source is USDA FoodData Central. When an important value is absent and a compatible official record exists, it may use supplementary data from the United Kingdom's CoFID.34

A value is not borrowed because two foods merely sound similar. Food identity, preparation, edible portion, nutrient meaning, unit, and measurement basis must be compatible. WoofChef keeps the source and any conversion applied.

Accepted analytical, calculated, imputed, reported, and literature-derived values count normally when their meaning and source are sound. Those labels describe provenance, not discounted NRC math.

Primary source

USDA FoodData Central

Used with an exact food and preparation match where one is available.

Supplementary source

CoFID

Used when an official UK record supplies a compatible missing value and the match is documented.

Product-specific items

Current label required

A supplement, premix, fortified food, or exact product needs a defensible current label and serving interpretation.

Natural variation

Real food varies

Species, season, soil, feeding, storage, trimming, cooking, and manufacturing can change nutrient content.
How food data becomes recipe dataFood identity, nutrient meaning, units, and reviewed conversions

Normalization

Meaning comes before conversion

Before a value enters recipe math, the food, preparation, nutrient identity, unit, and measurement basis must match a reviewed meaning. Accepted values are placed on a common per-100-gram as-fed basis and scaled to the recipe.

1 · Match the food

Identity and preparation

Raw or cooked, edible portion, skin, bone, draining, salt, and fortification must describe the profile used.

2 · Match the nutrient

Meaning before name

The nutrient definition, unit, and source basis must agree with what WoofChef intends to calculate.

3 · Convert explicitly

Only reviewed conversions

Units and biological forms are converted only through named rules.

4 · Scale the amount

From 100 g to your recipe

The value is multiplied by grams entered, divided by 100, and added to the total.

Missing data

What happens when a nutrient value is missing

A blank source field does not prove that a food contains none of that nutrient. WoofChef keeps a missing value distinct from a measured zero.

First, WoofChef looks for an exact compatible value from an approved source. If none exists, it asks whether that specific food-nutrient pair could materially change adequacy or safety.

For adequacy, accepted known values count and a noncritical missing contribution adds zero. That can show an MR shortfall, show that adequacy is not established against an AI, or preserve a calculated pass. Missing data never supplies hypothetical credit.

Safety is screened pair by pair. Missing Vitamin D or iodine can be critical for a particular marine food, concentrated fish product, seaweed, marine liver oil, liver, or supplement. It is not a global label applied to every similar-sounding food.

What WoofChef does when data is missing
  1. 1

    Look for a trustworthy match

    WoofChef checks for the same food, preparation, and nutrient from an approved source.

  2. 2

    Ask whether the missing number could change the result

    If it cannot meaningfully affect safety, WoofChef calculates with the known values and tells you what is missing.

  3. 3

    Do not guess when safety depends on it

    If the missing value could hide a safety problem, WoofChef says it cannot verify safety or leaves that ingredient out of Guided.

A missing value never adds nutrient credit to a recipe.

Known-excess rule: A confirmed safety excess remains an excess even when another part is uncertain. Missing evidence cannot turn “do not feed as-is” into a positive result.

05

Limits, warnings, and special cases

Safety and special rules

Hard ceilings remain distinct from advisories. Nutrient-form rules and technical thresholds are available when you want them.

Why Vitamin A is calculated differentlyRecognized activity for adequacy, preformed activity for safety

Vitamin A

One name can hide different compounds

WoofChef separates Vitamin A adequacy from upper-limit safety because food data can combine compounds that do not behave the same way in dogs.15

Adequacy

Minimum and target comparison

Accepted preformed Vitamin A plus estimated activity from accepted beta-carotene.

Upper-limit safety

Preformed activity only

Accepted preformed Vitamin A only. Beta-carotene-derived activity does not enter this safety channel.

FEDIAF canine conversion1 mg beta-carotene = 833 IU estimated Vitamin A activity

Preformed Vitamin A

Accepted retinol and reviewed retinyl forms count toward adequacy and the preformed upper-limit check.

Beta-carotene

Counts toward adequacy at exactly 833 IU per mg, but not toward the preformed safety check.

Alpha-carotene and beta-cryptoxanthin

No defensible dog-specific factor is available, so these receive no Vitamin A credit.

Human RAE or ambiguous total IU

Receives no canine credit unless the underlying forms can be separated and reviewed.
Other nutrition rules WoofChef appliesConditionals, ratios, combined nutrients, conversions, and dry matter

Conditionals and relationships

Some comparisons need more than one number

Targets that change with the recipe

More polyunsaturated fatty acids can raise Vitamin E. More protein can raise arginine. WoofChef currently raises zinc when high-phytate ingredients reach 15% or 30%, using 1.5x and 2x multipliers; this zinc rule remains under review.

Nutrient relationships and ratios

WoofChef checks calcium to phosphorus against 1:1 to 2:1, and linoleic acid to alpha-linolenic acid against 2.6:1 to 26:1. Failed or unresolvable hard relationships block a positive result.

Combined nutrients and conflicting routes

Combined amino acids count only when both components are known. Materially conflicting EPA and DHA routes withhold positive adequacy credit while preserving the larger supported safety amount.

Vitamin D and Vitamin E conversions

Accepted Vitamin D converts at 40 IU per microgram. Natural alpha-tocopherol in ordinary food converts at 1.49 IU of Vitamin E per milligram.

Native dry-matter safety limits

Sodium, chloride, and iodine remain on their native dry-matter basis. Recipe dry matter comes from the amount-weighted moisture of entered foods. No fixed calorie conversion is invented.

Exact products and approved active-dose modules

A branded product needs an exact current label, serving basis, and active form. Reviewed Guided modules can provide typed active doses for zinc, copper, choline, Vitamin D3, or calcium. Only the declared amount is credited.

Limits and warnings

How WoofChef handles safety limits and warnings

WoofChef checks known upper limits as well as targets. NRC Safe Upper Limits are published ceilings. A WoofChef safety ceiling is separate policy, clearly labelled. Other advisories and Guided rules draw attention to concerns or shape a generated recipe; they are not toxicity limits. Only a confirmed hard-limit excess produces “do not feed as-is.”

NRC upper limits

Published nutrient ceilings

Applicable NRC SULs are checked for preformed Vitamin A, Vitamin D, EPA+DHA, fat, and linoleic acid.

Dry-matter checks

Sodium, chloride, and iodine

Compared with actual recipe dry matter, not an invented calorie conversion.

WoofChef ceiling

Selenium

Clearly labelled as WoofChef policy, not an NRC SUL.

Advisories and guardrails

Warnings are not toxicity limits

Calcium, zinc, methionine, Guided fat, liver, and practical bounds stay separate from hard ceilings.
View exact thresholds and implementation details
Preformed Vitamin A, Vitamin D, EPA+DHA, fat, linoleic acidNRC limit for the selected comparison methodNRC SUL
Sodium and chloride15,000 mg/kg sodium; 23,500 mg/kg chloride on recipe dry matterNRC dry-matter SUL
Iodine4,000 micrograms/kg recipe dry matterWorking SUL with evidence note
Selenium500 micrograms per 1,000 kcalWoofChef safety ceiling

Selenium is WoofChef policy based on NRC's discussion of the AAFCO commercial-food limit, not an NRC adult-dog SUL.

For limits available on both methods, the selected method controls the result. Up to 101% is treated as at the limit for small calculation and rounding differences. This does not raise the limit.

Guided aims for no more than 98% of each hard ceiling, then checks the exact rounded recipe again.

Warnings, not hard SULs

Food-derived methionine: warning at 10x RA, stronger warning at 14x.

Calcium: warning at 2.5x RA, stronger warning at 4.5x. Ca:P remains the hard relationship.

Zinc: warning at 10x RA. NRC publishes no adult zinc SUL.

Phosphorus: no separate adult high warning; calcium and phosphorus are checked together.

Guided-only product rules

Healthy-adult fat: up to 40 g/1,000 kcal. Above 40 g is a caution and above 50 g a stronger caution. Missing fat data stops Guided.

Liver: 30 g/1,000 kcal, a provisional recipe-building rule rather than a toxicity threshold.

Ingredient bounds: practical minimums and maximums, not NRC toxicity limits.

Even after these checks, WoofChef cannot account for allergies, illness, medication interactions, contamination, unsafe preparation, individual tolerance, or every clinical factor.

06

Product and governance

Transparency and accountability

One Analyzer, neutral calculation, visible corrections, and an explicit review status.

One Analyzer

Analysis and Guided use the same final calculation

Analysis Mode

Evaluates the recipe you enter

You control the foods and amounts, choose metabolic weight or per 1,000 kcal, and inspect the detailed result.

Guided Builder

Creates a starter recipe for your dog

Guided uses metabolic weight, your choices and exclusions, and a reviewed ingredient list. Its practical rules are not additional NRC requirements.

Shared final check

Before Guided shows a recipe, WoofChef rounds every food and supplement amount, then checks that exact recipe again. The shown recipe is the one used when you save, print, or open it in Analysis Mode.

A generated recipe is not a veterinary prescription or product endorsement. A general supplement instruction counts only the named vitamin or mineral amount, not guessed product content.

Independence

Your recipe comes first

WoofChef is not paid to promote or recommend any particular product or supplement. Our core recipe checker is free to use, and we intend to keep it that way.

Specific products may appear in our database because their published nutritional profiles provide a practical reference for our calculation engine. Their inclusion does not mean that WoofChef endorses or recommends them.

When selecting products for inclusion, we aim to use products from reputable manufacturers that employ independent or third-party testing. However, users should not interpret the presence of any product in our database as an endorsement of its quality, safety, suitability, or effectiveness.

Corrections and review

Corrections should be visible

Found a possible error or a source that needs updating? Tell us what you found, the page or result involved, and the source you are relying on. We review substantiated corrections and record material public changes.

A methodology change should identify what changed, when, why, and whether it affected an earlier public explanation. Material claims should not be silently rewritten after people have relied on them.

Report a possible error

Send the result, page, and source through our Contact page.

Contact WoofChef

Primary references

Sources behind this methodology

Numbered citations point to original publications or official documentation. Statements about what WoofChef chooses, counts, excludes, or displays describe our methodology. WoofChef ceilings, warnings, and Guided guardrails are labelled as product policy rather than attributed to NRC.

  1. 1

    National Research Council, Nutrient Requirements of Dogs and Cats (2006)

    WoofChef’s primary nutrition comparison standard for healthy adult dogs at maintenance.

  2. 2

    AAFCO Dog and Cat Food Nutrient Profiles

    Official context for the purpose of AAFCO profiles, their NRC 2006 basis, and their role in commercial nutritional-adequacy claims.

  3. 3

    USDA FoodData Central

    WoofChef’s primary food-composition source.

  4. 4

    McCance and Widdowson’s CoFID 2021

    Official UK food-composition data used for compatible supplementary values where appropriate.

  5. 5

    FEDIAF Nutritional Guidelines 2025, Table VII-14

    Source of the specific canine beta-carotene conversion used by WoofChef.

  6. 6

    AAFCO Modified Atwater calorie calculation

    Source of the legacy Modified Atwater factors. WoofChef does not treat total dietary fiber as crude fiber.

  7. 7

    Canine zinc and copper interaction studies

    Primary canine research behind an interaction that cannot be reduced to one universal recipe formula.