Cat food phosphorus calculator
Label phosphorus per 1000 kcal, against kidney-disease limits
Why per 1000 kcal?
The same 0.15% is 1.67 g per 1000 kcal in a can (90 kcal/100 g) but 0.39 g in kibble (380 kcal/100 g) — over four times different. Cats eat to calories, so per 1000 kcal shows what they really take in.
See phosphorus by product in the food explorer → · Choosing a kidney diet →
Questions
How low should phosphorus be for kidney disease?
This calculator compares against 2.0 g per 1000 kcal for stages 1–2, 1.5 g for stage 3 and 1.2 g for stage 4 (the CatLab app’s kidney targets). Healthy adults need at least 1.25 g per 1000 kcal (AAFCO).
The label says phosphorus "min."
A minimum is a guarantee; the real value can be higher. A manufacturer’s typical analysis is more accurate if available.
Can I look up a product?
Yes — the CatLab food explorer shows phosphorus per 1000 kcal for each product and filters by kidney stage.
Estimates for healthy-weight cats based on NRC 2006 and IRIS guidance. A cat with a medical condition may need different numbers.