Dry Matter Calculator (Pet Food)

Pet food labels list nutrients as a percentage of the food as fed — but wet and dry foods contain very different amounts of water, making direct comparisons misleading. The Dry Matter Calculator removes moisture from the equation so you can compare foods fairly. Enter the Moisture Content and the as-fed percentages for Protein, Fat, Fiber, and Ash from your pet food label to get each nutrient recalculated on a dry matter basis, plus an estimated Carbohydrates value.

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Moisture percentage shown on pet food label

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Protein percentage on pet food label

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Fat percentage on pet food label

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Fiber percentage on pet food label

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Ash percentage if available on label

Results

Protein (Dry Matter Basis)

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Fat (Dry Matter)

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Fiber (Dry Matter)

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Ash (Dry Matter)

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Carbohydrates (Estimated)

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Frequently Asked Questions

What is dry matter basis and why is it important for pet food comparison?

Dry matter basis removes water content from nutritional calculations, allowing accurate comparison between foods with different moisture levels. This is essential when comparing wet food (75-80% moisture) to dry food (10% moisture).

How do I calculate dry matter content from as-fed percentages?

Use the formula: Dry Matter % = (As-Fed % × 100) ÷ (100 - Moisture %). For example, if protein is 26% as-fed and moisture is 10%, then dry matter protein = (26 × 100) ÷ (100 - 10) = 28.9%.

Where can I find the moisture content on pet food labels?

Moisture content is listed in the guaranteed analysis section of pet food labels. Dry foods typically contain 8-12% moisture, while canned foods contain 75-85% moisture.

Can I compare wet and dry pet foods using this calculator?

Yes, that's exactly what this calculator is designed for. By converting both foods to dry matter basis, you can directly compare their nutritional content regardless of moisture differences.

What are guaranteed analysis values on pet food labels?

Guaranteed analysis shows minimum percentages for protein and fat, and maximum percentages for fiber and moisture. These are regulatory requirements but actual values may be higher than minimums listed.

How accurate is the carbohydrate estimation?

Carbohydrates are estimated by subtracting protein, fat, fiber, ash, and moisture from 100%. This gives a reasonable approximation, though actual carbohydrate content may vary slightly.

Should I include ash in my calculations?

Including ash (mineral content) provides more accurate results if available on the label. If ash isn't listed, the calculator will estimate it as part of the remaining dry matter content.

Is it safe to add water to dry dog food?

Yes, adding water to dry food is generally safe and can help with hydration. However, this changes the as-fed percentages, so use dry matter basis calculations to understand the actual nutritional content.