Cat Food Label Calculator
Understand your cat food label with estimated carbohydrates and moisture-adjusted nutrient percentages — all in one simple tool.
Analyze Your Cat Food
Enter percentages from the same product. For the most useful estimate, request the manufacturer’s typical or average nutrient analysis rather than relying only on minimum and maximum label guarantees.
Your Nutrition Analysis
Calculated from the values entered.
| Component | As fed | Dry matter |
|---|---|---|
| Protein | — | — |
| Fat | — | — |
| Crude fiber | — | — |
| Ash | — | — |
| Estimated carbohydrate (NFE) | — | — |
What Does This Calculator Measure?
It estimates carbohydrate by difference (also called nitrogen-free extract, or NFE) and converts as-fed nutrient percentages to a dry-matter basis. The conversion helps compare foods with different water content. It does not measure digestibility, calories from carbohydrate, ingredient quality, or whether a diet is complete and balanced.
How the Calculation Works
100 − moisture %The percentage remaining after water is excluded.
100 − protein − fat − fiber − moisture − ashAn estimate by difference, not a direct carbohydrate laboratory measurement.
(as-fed nutrient ÷ dry matter) × 100Applies to protein, fat, crude fiber, ash, and estimated carbohydrate.
Example: 40% protein, 15% fat, 3% crude fiber, 10% moisture and 7% ash gives 25% estimated carbohydrate as fed, 90% dry matter, and approximately 27.8% estimated carbohydrate on a dry-matter basis.
Why Guaranteed Analysis Has Limits
In US pet food labeling, crude protein and crude fat are generally guaranteed minimums, while crude fiber and moisture are maximums. Ash, when guaranteed, is generally a maximum. Combining these limits does not give the food’s actual composition. The manufacturer’s typical or average analysis is more informative for comparisons. AAFCO explains label guarantees.
Do not treat the estimated carbohydrate percentage as a verified laboratory value or assume that a lower result means a food is better for every cat. Crude fiber also does not include all dietary fiber.
As-Fed vs. Dry-Matter Basis
As-fed percentages include water. Dry-matter percentages mathematically remove water, which makes it easier to compare a wet food and a dry food. A food with 80% moisture contains 20% dry matter; 10% as-fed protein therefore corresponds to 50% protein on a dry-matter basis. The FDA provides examples of this conversion.
Frequently Asked Questions
Can I leave ash blank?
No. Ash is part of the subtraction formula. If it is not listed, ask the manufacturer for its typical ash content rather than treating an unknown amount as zero.
Does this calculator measure carbohydrate calories?
No. Carbohydrate percentage by weight is not the same as the percentage of calories supplied by carbohydrate. That requires additional energy calculations and suitable nutrient data.
Why is a guaranteed-analysis estimate approximate?
Protein and fat guarantees are usually minimums, while fiber and moisture are usually maximums. These values are not necessarily the measured values for the same batch.
Can I compare wet and dry cat food?
Dry-matter conversion helps compare nutrient percentages across foods with different moisture content. For a fuller nutritional comparison, consider calories, nutritional adequacy and your cat’s individual needs.
Does a low carbohydrate estimate prove that a food is healthy?
No. Carbohydrate by difference is one limited measurement and cannot assess complete nutritional suitability.
Sources & References
Related MyyCat Tools & Guides
Want More Practical Cat-Care Guidance?
Explore the Complete Cat Care Manual for everyday nutrition, feeding, grooming and behavior guidance. This is a paid digital product sold through an external storefront.
Explore the Complete Cat Care Manual →Browse MyyCat BooksMyyCat · Educational calculator. Review the food label and consult your veterinarian when needed.