As-fed nutrient
This is the nutrient guarantee as a percentage of the product including moisture.
Pet-food label comparison
Dog Food Dry-Matter Calculator
Convert protein, fat, fibre or another guaranteed-analysis value from an as-fed percentage to a moisture-free basis. This supports a fairer concentration comparison between foods with different moisture levels.
FDA-described methodAny label nutrientWorks for wet and dry foodNo product ranking
Interactive tool
Calculated in your browserConvert a label value to dry matter
Enter the product's moisture percentage and one nutrient percentage exactly as shown in its guaranteed analysis.
Moisture78.0% as fedDry matter22.0% of foodNutrient on dry-matter basis54.5% dry matter
Use values from the same product label. Guaranteed-analysis minima and maxima are not the same as exact laboratory measurements.
What your results mean
Dry-matter share
Subtracting moisture from 100 estimates the percentage of the product that remains on a moisture-free basis.
Dry-matter nutrient
The nutrient value divided by dry matter and multiplied by 100. Compare like-for-like guarantees between products.
How this calculator works
1. Find dry matter
dry matter % = 100 − moisture %A product labelled 78% moisture therefore contains 22% dry matter for this label-based calculation.
2. Divide the nutrient
nutrient % ÷ dry matter %The as-fed nutrient guarantee is divided by the calculated dry-matter percentage.
3. Convert back to percent
ratio × 100Multiplying the ratio by 100 expresses the nutrient as a percentage of dry matter.
4. Compare equivalent values
Use the same nutrient and the same guarantee type across products. A crude-protein minimum should not be treated as equivalent to an exact analysis value.
Food with 78% moisture and 12% crude protein
The food contains 22% dry matter because 100 − 78 = 22. Dividing 12 by 22 and multiplying by 100 gives approximately 54.5% crude protein on a dry-matter basis.
Factors that change the result
Moisture guarantee
A higher listed moisture percentage produces a smaller dry-matter share and therefore a larger converted nutrient percentage for the same as-fed value.
Guarantee type
Labels may state minimums for protein and fat and maximums for moisture and fibre. These are boundaries rather than exact measurements.
Calories and portions
Dry-matter percentage does not account for energy density or how much food a dog eats, so it cannot compare actual daily nutrient intake by itself.
Concentration is not a nutritional recommendation
This conversion does not determine whether a food is complete, balanced or suitable for a particular dog. It does not evaluate ingredient quality, digestibility, calories, nutrient interactions or medical needs. Ask a veterinarian or qualified veterinary nutrition professional about diet selection for disease, growth, pregnancy or other special requirements.
Dog Food Dry-Matter Calculator FAQs
What is dry matter in dog food?
Dry matter is the portion remaining after moisture is removed mathematically. Expressing a nutrient against that portion makes products with different moisture levels easier to compare.
Why can the dry-matter nutrient percentage be higher than the label value?
The label value includes water in the product weight. Removing water from the comparison reduces the denominator, so the nutrient represents a larger percentage of the remaining dry matter.
Where do I find moisture and nutrient percentages?
Use the guaranteed analysis on the same product label. Enter the moisture percentage and the listed percentage for protein, fat, fibre or another nutrient you are comparing.
Can I compare wet and dry dog food?
Dry-matter conversion helps compare listed nutrient concentrations when foods contain very different moisture levels. It does not by itself compare calories, ingredient quality, digestibility or overall suitability.
Does a guaranteed minimum equal the exact amount?
No. A guaranteed minimum or maximum is a label guarantee, not necessarily the product's exact laboratory value. Compare the same type of guarantee between products and interpret small differences cautiously.
Does a higher percentage mean a food is better?
No. A higher dry-matter percentage describes concentration only. Nutritional suitability depends on the dog, the complete diet, energy intake and other nutrients—not one number alone.
Sources and review record
U.S. Food and Drug Administration
The FDA explains that guaranteed analysis is expressed as-fed and provides the dry-matter conversion method and a worked comparison.
Open source →The Dogs Mag calculator methodology
Internal calculation, validation, review and correction policy.
Open source →- Method version
- pet-food-dry-matter-fda-v1
- Last reviewed
- 27 July 2026
- Reviewed by
- The Dogs Mag Editorial Team
- Review scope
- FDA formula transcription, validation and explanatory content
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