Worked examples
Three hand-checked examples showing the full calculation, so you can verify the tool against your own math.
Example 1 — Kibble protein to dry matter basis
A dry kibble lists 25% crude protein and 10% moisture (as fed).
- Dry matter % = 100 − 10 = 90%
- Protein DM = (25 ÷ 90) × 100 = 27.78%
27.78% protein on a dry matter basis
Example 2 — Wet food beats kibble (the classic surprise)
A canned food lists 8% protein at 75% moisture; a kibble lists 25% protein at 10% moisture. On the shelf the kibble looks 3× better.
- Canned: dry matter = 100 − 75 = 25% → (8 ÷ 25) × 100 = 32.0%
- Kibble: dry matter = 100 − 10 = 90% → (25 ÷ 90) × 100 = 27.78%
Wet food: 32.0% DM protein > kibble: 27.78% DM protein
The water was hiding the truth — per gram of actual food, the canned product is more protein-dense.
Example 3 — Reverse: formulating a 60%-moisture ration
You want a total mixed ration to deliver 30% protein on a dry matter basis, and the mix will be 60% moisture.
- Dry matter fraction = 1 − 60/100 = 0.40
- Protein as fed = 30 × 0.40 = 12%
Target 12% protein as fed on the scale
Methodology & formulas
All conversions in this tool use the standard dry matter basis identities taught in animal nutrition references (e.g. NRC Nutrient Requirements series):
dry matter % = 100 − moisture %
nutrientDM = nutrientas-fed ÷ (1 − moisture/100)
nutrientas-fed = nutrientDM × (1 − moisture/100)
Energy and cost scale the same way, because water dilutes everything equally:
kcal per kg DM = (kcal per 100 g as-fed × 10) ÷ (1 − moisture/100)
cost per kg DM = price per kg as-fed ÷ (1 − moisture/100)
Forage moisture bands in the advisor follow common cooperative-extension rules of thumb: dry hay below ~15%, haylage 40–60%, chopped silage 60–70%. They are starting points, not lab prescriptions — curing method, bale density, and climate all shift the safe window.
Why as-fed percentages mislead
Guaranteed Analysis panels are legally required to show percentages as fed, water included. A canned food that is 78% water has less than a quarter of its weight available as nutrients, while a kibble at 10% moisture is highly concentrated. Comparing 9% vs 26% protein across those two labels compares water, not food. An as-fed vs dry matter conversion, as in the table below, is the only fair comparison:
Wet food at 78% moisture vs kibble at 10% moisture — same nutrients, honest basis:
| Nutrient | Wet food | Kibble |
|---|
| Protein | 9% as fed
40.9% DM | 26% as fed
28.9% DM |
| Fat | 5% as fed
22.7% DM | 14% as fed
15.6% DM |
On a dry matter basis the ranking flips: the wet food is more nutrient-dense. This does not make it “better” overall — calories, digestibility, price, and your animal's needs all matter — but it makes the comparison honest.