# What is my UACR?

Divides urine albumin by urine creatinine to give the albumin-to-creatinine ratio (UACR) in mg/g and mg/mmol, and places it in the KDIGO albuminuria categories A1 to A3.

- Page: https://www.acalculator.org/health/uacr-calculator
- JSON spec: https://www.acalculator.org/health/uacr-calculator.json
- Version: ece581f1a041

## Default answer

Example with the default inputs (Units mg/dL and mg/dL, Urine albumin (mg/dL) 1.5, Urine creatinine (mg/dL) 100): Urine albumin-to-creatinine ratio: 15.0 mg/g (1.7 mg/mmol), A1: under 30 mg/g.

## Inputs

| Key | Label | Description |
| --- | --- | --- |
| units | Units | Albumin and creatinine both in mg/dL; albumin in mg/L with creatinine in mg/dL; or SI units (albumin in mg/L, creatinine in mmol/L). |
| alb | Urine albumin (mg/dL) | Albumin in the urine sample, 0 to 1,000 mg/dL. |
| albL | Urine albumin (mg/L) | Albumin in the urine sample, 0 to 10,000 mg/L (1 mg/L is 1 µg/mL). |
| cr | Urine creatinine (mg/dL) | Creatinine in the same urine sample, 1 to 1,000 mg/dL. |
| crSi | Urine creatinine (mmol/L) | Creatinine in the same urine sample, 0.1 to 90 mmol/L. |

## Outputs

| Key | Label | Description |
| --- | --- | --- |
| category | KDIGO albuminuria category | A1, A2, or A3, read from the ratio shown in the unit you typed (mg/g, or mg/mmol for SI). |
| mgG | UACR (mg/g) | mg of albumin per g of creatinine, to 1 decimal (from SI units: mg/mmol ÷ 0.113). |
| mgMmol | UACR (mg/mmol) | mg of albumin per mmol of creatinine, to 1 decimal (from mg/g: × 0.113). |

## Method

UACR (mg/g) = urine albumin (mg/dL) ÷ urine creatinine (mg/dL) × 1,000, or albumin (mg/L) ÷ creatinine (mg/dL) × 100; in SI units, UACR (mg/mmol) = albumin (mg/L) ÷ creatinine (mmol/L). Rounded once to 1 decimal, halves up; the category reads the rounded ratio in the unit typed. mg/mmol = mg/g × 0.113.

## Assumptions

- Albumin and creatinine are measured in the same urine sample; an early morning sample is preferred (KDIGO 2012).
- The other unit uses the KDIGO factor 0.113 mg/mmol per mg/g, so the two categories can differ near a cut-off.
- One raised result is not a diagnosis: kidney damage needs a raised result that lasts more than 3 months.

## Worked examples

1. units = us, alb = 1.5, cr = 100 gives category = A1: under 30 mg/g, mgG = 15.0, mgMmol = 1.7. Source: KDIGO 2012 CKD guideline, Chapter 1 (https://pmc.ncbi.nlm.nih.gov/articles/PMC4089693/).
2. units = us, alb = 6, cr = 120 gives category = A2: 30 to 300 mg/g, moderately increased, mgG = 50.0, mgMmol = 5.7.
3. units = us, alb = 3, cr = 100 gives category = A2: 30 to 300 mg/g, moderately increased, mgG = 30.0, mgMmol = 3.4.
4. units = us, alb = 30, cr = 100 gives category = A2: 30 to 300 mg/g, moderately increased, mgG = 300.0, mgMmol = 33.9.
5. units = mgl, albL = 450, cr = 75 gives category = A3: over 300 mg/g, severely increased, mgG = 600.0, mgMmol = 67.8.
6. units = si, albL = 25, crSi = 8 gives category = A2: 3 to 30 mg/mmol, moderately increased, mgG = 27.7, mgMmol = 3.1.
7. units = si, albL = 5, crSi = 10 gives category = A1: under 3 mg/mmol, mgG = 4.4, mgMmol = 0.5.
8. units = us, alb = 30.005, cr = 100 gives category = A3: over 300 mg/g, severely increased, mgG = 300.1, mgMmol = 33.9.

## FAQ

### How is UACR calculated?

Divide the urine albumin in mg by the urine creatinine in g, both from the same sample. With both in mg/dL: albumin ÷ creatinine × 1,000. For 6 mg/dL of albumin and 120 mg/dL of creatinine: 6 ÷ 120 × 1,000 = 50 mg/g. In SI units the ratio is albumin (mg/L) ÷ creatinine (mmol/L), in mg/mmol.

### What is a normal UACR?

Under 30 mg/g (under 3 mg/mmol), the KDIGO category A1. KDIGO 2012 calls 30 mg/g or more increased, about 3 times the normal value, and links it to a higher risk of complications of chronic kidney disease (CKD).

### What do A1, A2, and A3 mean?

They are the KDIGO 2012 albuminuria categories. A1 is under 30 mg/g; A2 is 30 to 300 mg/g, which the National Kidney Foundation calls moderately increased albuminuria (once called microalbuminuria); A3 is over 300 mg/g, severely increased (once called macroalbuminuria). In mg/mmol the cut-offs are 3 and 30.

### Does one high UACR mean kidney disease?

No. KDIGO 2012 defines CKD by kidney damage that lasts more than 3 months, and says a raised ratio can be short-lived and caused by other things. A raised result on a random sample is confirmed with an early morning sample; the National Kidney Foundation describes kidney damage as two positive tests over 3 or more months.

### How do I convert mg/g to mg/mmol?

Multiply by 0.113, the factor KDIGO 2012 gives. So 30 mg/g is about 3.4 mg/mmol. KDIGO rounds the SI cut-off to 3 mg/mmol, so a ratio near a cut-off can fall in different categories in the two units. This page uses the cut-offs of the unit you typed.

### My lab reports albumin in mg/L or µg/mL. Which option do I pick?

mg/L and µg/mL are the same. Pick "mg/L and mg/dL" if creatinine is in mg/dL, or "SI" if creatinine is in mmol/L. 10 mg/L of albumin is 1 mg/dL.

### Why use a ratio rather than the albumin alone?

Urine can be dilute or concentrated. Dividing by creatinine corrects for that, so a spot sample stands in for a 24-hour collection: NIDDK notes that UACR in mg/g is about the albumin excreted in mg per day.

## Sources

- Kidney Disease: Improving Global Outcomes (KDIGO) CKD Work Group. KDIGO 2012 Clinical Practice Guideline for the Evaluation and Management of Chronic Kidney Disease. Chapter 1: Definition and classification of CKD. Kidney Int Suppl. 2013;3(1):19-62 (CKD present for more than 3 months; ACR ≥30 mg/g [≥3 mg/mmol] increased; A3 >300 mg/g or >30 mg/mmol; "To convert ACR in mg/g to mg/mmol multiply by 0.113"; transient rises). https://doi.org/10.1038/kisup.2012.64 (full text: https://pmc.ncbi.nlm.nih.gov/articles/PMC4089693/, retrieved 2026-10-19)
- KDIGO 2012 CKD guideline, Summary of Recommendation Statements. Kidney Int Suppl. 2013;3(1):5-14 (1.4.4.1: ACR first, early morning urine preferred; 1.4.4.3: confirm ACR ≥30 mg/g on a random sample with an early morning sample). https://doi.org/10.1038/kisup.2012.77 (full text: https://pmc.ncbi.nlm.nih.gov/articles/PMC4284512/, retrieved 2026-10-19)
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Assess Urine Albumin (UACR (mg/g) = urine albumin (mg/dL) ÷ urine creatinine (g/dL); about equal to albumin excretion in mg per day). https://www.niddk.nih.gov/health-information/professionals/clinical-tools-patient-management/kidney-disease/identify-manage-patients/evaluate-ckd/assess-urine-albumin (retrieved 2026-10-19)
- National Kidney Foundation. ACR (albumin in mg ÷ creatinine in g; moderately increased albuminuria 30 to 300 mg/g, severely increased above 300; two positive tests over 3 or more months). https://www.kidney.org/node/23763 (retrieved 2026-10-19)