IRIS CKD Staging Calculator for Dogs & Cats (2026)
Stage chronic kidney disease from creatinine (and SDMA), and substage by proteinuria (UPC) and systolic blood pressure — IRIS 2026 thresholds.
Results are calculated in your browser. Always double-check before administering and use your clinical judgement.
How it is calculated
Stage on a fasting, hydrated, stable patient [1].
| Stage | Dog creatinine | Cat creatinine | Dog SDMA | Cat SDMA |
|---|---|---|---|---|
| 1 | < 125 µmol/L (< 1.4 mg/dL) | < 140 µmol/L (< 1.6 mg/dL) | < 18 | < 18 |
| 2 | 125–250 (1.4–2.8) | 140–250 (1.6–2.8) | 18–35 | 18–25 |
| 3 | 251–440 (2.9–5.0) | 251–440 (2.9–5.0) | 36–54 | 26–38 |
| 4 | > 440 (> 5.0) | > 440 (> 5.0) | > 54 | > 38 |
Persistently raised SDMA moves the stage up: dogs — SDMA > 18 in stage 1, > 35 in stage 2, > 54 in stage 3; cats — SDMA > 18 in stage 1, > 25 in stage 2, > 38 in stage 3 → stage and treat as the next stage [1].
UPC: dogs < 0.2 non-proteinuric, 0.2–0.5 borderline, > 0.5 proteinuric; cats < 0.2, 0.2–0.4, > 0.4 [1]. Systolic BP: < 140 normotensive, 140–159 prehypertensive, 160–179 hypertensive, ≥ 180 mmHg severely hypertensive [1].
Worked example
Dog, creatinine 2.0 mg/dL (177 µmol/L) → IRIS stage 2.
Frequently asked questions
What creatinine is IRIS stage 2 in dogs?
Stage 2 in dogs is 125–250 µmol/L (1.4–2.8 mg/dL); in cats 140–250 µmol/L (1.6–2.8 mg/dL) [1].
How does SDMA change the IRIS stage?
If SDMA is persistently above 18 µg/dL in a stage 1 patient, the patient is staged and treated as stage 2; similar rules apply between the other stages [1].
What UPC is proteinuric?
A UPC above 0.5 in dogs and above 0.4 in cats is proteinuric; below 0.2 is non-proteinuric [1].
More calculators
References
For veterinary professionals. Information supports — never replaces — clinical judgement; always check the current product label and local regulations.