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Dry Matter Basis Calculator

Compare wet and dry pet foods fairly by removing the water from the label percentages.

✔ Reviewed by a licensed veterinarianContent updated 18 Oct 2026Reviewed 18 Oct 2026Sources: AAFCO Dog & Cat Food Nutrient Profiles / label guidance · NRC
Dry Matter Basis CalculatorFree · instant
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Quick answer. To compare foods fairly, remove the water: a wet food with 8% protein and 78% moisture has 36.4% protein on a dry matter basis (8 ÷ (100 − 78) × 100). Use the as-fed percentages from the guaranteed analysis and the moisture value from the same label.

How to use the dry matter basis calculator

  1. Enter moisture % from the label.
  2. Enter protein, fat and/or fibre %.
  3. Press Calculate.

Worked example

A wet food with 78% moisture, 8% protein, 5% fat and 1.5% fibre on the label.

Moisture % (label)
78
Protein %
8
Fat %
5
Fibre %
1.5
36.4% protein
Protein (dry matter)
36.4%
Fat (dry matter)
22.7%
Fibre (dry matter)
6.8%

Example values are illustrative; this result is produced by the same calculator above.

How we calculate it

Nutrient on DM basis (%) = as-fed % ÷ (100 − moisture %) × 100

Sources: AAFCO Dog & Cat Food Nutrient Profiles / label guidance · NRC

Understanding your result

Pet food labels give nutrients as fed, including water. Wet food contains a lot of water, which makes its protein and fat look low compared with dry kibble.

Dry matter basis removes the water so that foods can be compared fairly. The formula is the as-fed percentage divided by (100 minus the moisture percentage), multiplied by 100.

For example, a wet food with 8% protein and 78% moisture has 36.4% protein on a dry matter basis.

Common mistakes

  • Comparing as-fed numbers of wet and dry foods.
  • Using the wrong moisture figure; use the maximum moisture on the label.
  • Treating dry matter percentages as a measure of quality by themselves.

Good to know

  • Dry matter values are for comparing foods, not for deciding portions.
  • Check that the food is complete and balanced for your pet's life stage.
  • If your pet has a health condition, choose food with your vet.

Frequently asked questions

What is dry matter basis?

The nutrient percentage after removing water, so foods with different moisture can be compared.

How do I calculate it?

Dry matter % = as-fed % ÷ (100 − moisture %) × 100.

Why does wet food look low in protein?

Because it is mostly water. On a dry matter basis it can be as high as or higher than kibble.

Why compare foods on a dry matter basis?

Moisture differs a lot between wet and dry food. Removing the water shows the nutrient content on equal terms, so you can compare a can with a bag of kibble.

Where do I find moisture on the label?

It is in the guaranteed analysis as maximum moisture. Use the as-fed percentages for protein, fat and fibre from the same panel.

Is a higher dry matter protein always better?

Not necessarily. Needs depend on life stage and health, so use the numbers to compare foods and ask your vet what suits your dog.

Reviewed by a licensed veterinarian
Last reviewed 18 Oct 2026 · How we review

Sources

  1. AAFCO Dog & Cat Food Nutrient Profiles / label guidance
  2. NRC (2006) Nutrient Requirements of Dogs and Cats, National Academies Press
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Estimates only. Every pet is different — confirm with your veterinarian.