Dry Matter Basis Calculator

What is “dry matter basis” and why is it important?

When comparing pet foods we often look at the labels to see which food has more protein, less fat, etc. Pet food nutrition labels give the percentages on an as-fed basis. This simply means it’s based on the breakdown of the food as it is in the package.

However, comparing pet food this way can often be misleading.

If you’re comparing a dry food to another dry food, or a canned food to another canned food, it doesn’t really matter much.

According to the FDA:

“To make meaningful comparisons of nutrient levels between a canned and dry product, they should be expressed on the same moisture basis.”

Therefore, if you’re comparing a dry food, which is typically 10% moisture, to a canned food that’s 75% moisture it won’t be an equal comparison. To get the true nutrient levels in a food you need to factor out 100% of the moisture.


Let’s say you have a dry kibble that reads 30% protein on the label and you’re comparing it to a canned food that reads 10% protein on the label.

By simply comparing labels (as-fed basis) it seems like the dry food has way more protein than the canned.

However, when you factor out the moisture from each product (dry matter basis) you find that the protein in the dry food is 33.33% and the protein in the canned food is actually 40%.

Understanding dry matter basis becomes even more important (and potentially life saving) when you have a pet with special dietary needs, such as low protein or low fat.

Dry Matter Calculator

To calculate the dry matter basis of any food simply fill out the fields below based on the food label’s guaranteed analysis.

Single Nutrient Dry Matter Calculator

If you need to figure out the dry matter basis for a single nutrient (i.e. phosphorous) use this calculator.