Calculate urine ACR from albumin and creatinine in the same specimen. Check the laboratory units before entering values.
Values are calculated on this page only; they are not sent to or saved on a server.
What does urine ACR measure?
ACR, also called uACR, is urine albumin concentration divided by urine creatinine concentration in the same sample. Albumin is a blood protein; increased urinary albumin can be a sign of kidney damage. Using a ratio helps account for how concentrated or dilute a urine sample is.
ACR and eGFR measure different aspects of kidney health. Albuminuria can be present even when eGFR is relatively high. Interpret both measures, their trends, and the clinical context together.
Three things to check on the laboratory report
- Specimen: both inputs must come from the same urine sample. Do not use the serum creatinine value used for eGFR or CrCl.
- Units: enter urine albumin in mg/L, then select mg/dL or mmol/L for urine creatinine. If albumin is reported in mg/dL, multiply it by 10 to obtain mg/L.
- Already-reported ratio: if the laboratory has supplied ACR in mg/g or mg/mmol, do not enter that ratio as an albumin concentration and calculate it again. Review the laboratory's result.
Total urine protein and the protein-to-creatinine ratio (PCR) are also different from albumin and ACR. Check the test name carefully. A result reported as below a detection limit cannot be turned into an exact concentration by guessing a number. This calculator accepts positive numeric values; discuss limited or qualified results with the laboratory.
Formula and unit conversion
With urine creatinine in mg/dL, ACR (mg/g) = 100 × urine albumin (mg/L) / urine creatinine (mg/dL). The factor of 100 accounts for converting creatinine from mg/dL to g/L.
With creatinine in mmol/L, use ACR (mg/g) = albumin (mg/L) / [creatinine (mmol/L) × 0.11312]. The calculator multiplies mg/g by 0.11312 to show a corresponding mg/mmol value. Those two outputs express one result in different units.
Worked example and A1–A3 categories
Urine albumin 30 mg/L and urine creatinine 100 mg/dL give 100 × 30 / 100 = 30 mg/g, approximately 3.4 mg/mmol. A result of exactly 30 mg/g belongs to A2 under the KDIGO mg/g categories used here.
| Category | ACR (mg/g) | Description |
|---|---|---|
| A1 | Below 30 | Normal to mildly increased |
| A2 | 30 through 300 | Moderately increased |
| A3 | Above 300 | Severely increased |
Classification uses the unrounded mg/g result. Exactly 300 mg/g is A2; greater than 300 is A3. KDIGO's conventional mg/mmol cutoffs are rounded, so they do not exactly match a decimal conversion at every boundary. The category label on this page is based on mg/g.
Does one high result mean chronic kidney disease?
A single elevated ratio does not establish chronic kidney disease. Evaluation considers whether abnormalities persist for at least three months, eGFR, the cause, and other markers of kidney damage. A clinician may confirm an elevated ACR with a first-morning urine sample or other appropriate follow-up.
Strenuous exercise, fever or infection, urinary infection, menstrual contamination, and dehydration can affect a result. Explain the conditions around testing and bring previous results. The three-month chronicity criterion is not an instruction to ignore a new high result or symptoms for three months.
Prepare useful information for a clinical review
- Keep the test date, separate albumin and creatinine units, and any laboratory-reported ACR together.
- Bring previous ACR and eGFR results, blood-pressure records, and relevant diabetes results if available.
- Mention intense exercise before testing, fever, urinary symptoms, menstruation, and current medicines.
Do not start, stop, or change medication from this calculation. Decisions about the cause of albuminuria and treatment depend on trends and individual circumstances.
Frequently asked questions
Does A2 mean stage 2 kidney disease?
No. A is the albuminuria category; eGFR uses a different G classification. A2 alone cannot establish the cause or stage of chronic kidney disease.
If eGFR looks normal, can I ignore ACR?
The tests provide complementary information. The creatinine and eGFR guide explains why urine albumin matters alongside filtration estimates.
Related calculators and sources
eGFR calculator · CrCl calculator · All health calculators · 한국어
- KDIGO 2024 CKD guideline: albuminuria and confirmation
- NIDDK: assessing urine albumin
- National Kidney Foundation: uACR preparation and interpretation
Prepared and sources checked by Life Choice Note, 26 September 2026. This is general education checked against the cited sources, not independently physician-reviewed guidance or an individual diagnosis, treatment, or exercise prescription. Editorial standards · Terms and disclaimer