Estimated carbohydrate

2,000 estimates · 1,632 rest on an assumed ash figure

No pet food label states carbohydrate. It is worked out by subtracting everything that is stated — protein, fat, fibre, moisture and ash — from 100, a figure nutritionists call nitrogen-free extract. We publish it on 2,000 of 2,354 labels, and here is the part almost nobody discloses: on 1,632 of those (82%) the ash term is an assumption, because only 375 labels (15.9%) print ash at all.

Why the ash term matters

Ash is the mineral residue — calcium, phosphorus and the rest. It is typically 6–8% of a dry food and higher in some wet ones, so getting it wrong shifts the carbohydrate estimate by several points in the same direction every time. That is enough to move a food across a threshold someone is shopping on.

Where a brand publishes ash we use the published figure. Where it does not, we substitute a typical value for the form and flag the estimate on the product page. We would rather show you an estimate with its assumption stated than a number that looks authoritative and is not.

Why nobody prints it

Because they are not required to. AAFCO mandates protein, fat, fibre and moisture; ash is optional, and carbohydrate is not a required guarantee at all. A category that markets heavily on "grain-free" and "low carb" has no obligation to tell you the carbohydrate content, which is a gap worth knowing about before you read any marketing claim about it.

How to use the number

Treat it as a band, not a point. A food estimated at 28% carbohydrate is meaningfully different from one at 8%, and probably not meaningfully different from one at 31%. Where the estimate carries an assumed ash value, treat the band as wider still.

For cats the number matters more than for dogs — an obligate carnivore has no dietary requirement for carbohydrate — which is why the cat pages lead with it.

Frequently asked

Why is carbohydrate not on the pet food label?

It is not a required guarantee. AAFCO requires crude protein, crude fat, crude fibre and moisture. Carbohydrate is worked out by subtraction, and ash — one of the terms you need — is itself optional.

How accurate is an estimated carbohydrate figure?

It is as good as its ash term. With ash published the estimate is tight; with ash assumed it can be a few points out. Only 15.9% of the labels we have verified publish ash, so most estimates anywhere on the internet carry this assumption whether or not the site says so.

What is a low-carbohydrate cat food?

Commonly under about 10% on a dry-matter basis, which in practice means a wet food — dry cat foods need starch to hold the kibble together and typically land far higher.

Related

See it applied

Every figure discussed here is computed on each product page from that food’s own verified label, with gaps marked rather than filled. Start with every priced dog food ranked by cost per 1,000 kcal, browse every verified cat food, or read what is actually in pet food — ingredient prevalence counted across all 2,354 labels. The full extraction method is in the methodology.