# Albumin to Creatinine Ratio Calculator (ACR)

URL: https://speedycalculator.com/calculators/health/acr/
Last updated: 2026-10-30

> The albumin to creatinine ratio calculator divides urine albumin by urine creatinine from a spot urine sample to detect kidney damage, converts between mg/g and mg/mmol, and gives the KDIGO albuminuria category.

## Inputs

- Urine albumin (mg/dL, mg/L)
- Urine creatinine (mg/dL, mmol/L)

## Results

- ACR
- ACR in mg/mmol

## Formula

```
ACR (mg/g) = urine albumin (mg/dL) ÷ urine creatinine (mg/dL) × 1000
mg/mmol = mg/g ÷ 8.84
A1 < 30 mg/g · A2 30–300 mg/g · A3 > 300 mg/g
```

## Explanation

Albumin in the urine is an early sign of kidney damage from diabetes or high blood pressure, and it predicts heart disease too. A spot ACR avoids a 24-hour urine collection. KDIGO combines the ACR category with the GFR category to grade CKD risk.

### How to use the Albumin to Creatinine Ratio Calculator

- **Urine albumin**
- **Urine creatinine**

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Enter the urine albumin and creatinine from the same sample. An abnormal result should be confirmed in 2 of 3 samples over 3–6 months.

### Albuminuria categories (KDIGO)

Categorymg/gmg/mmolDescriptionA1below 30below 3Normal to mildly increasedA230–3003–30Moderately increasedA3above 300above 30Severely increased

### Inputs explained

FieldWhat to enterUrine albuminUnits: mg/dL, mg/LUrine creatinineUnits: mg/dL, mmol/L

### What each result means

- **ACR** = [Urine albumin]÷[Urine creatinine]×1000
- **ACR in mg/mmol** = [ACR]÷8.84

*Health note: this calculator is for education and screening only and is not a diagnosis or treatment advice. Discuss your results with a qualified clinician.*

## Worked example

Inputs — Urine albumin: 4 mg/dL; Urine creatinine: 100 mg/dL.

Results — **ACR = 40 mg/g**; ACR in mg/mmol = 4.5 mg/mmol.

## Key terms

- **Albuminuria**: Albumin in the urine.

## FAQ

**What is a normal ACR?**
Below 30 mg/g (3 mg/mmol).

**What raises ACR temporarily?**
Exercise, fever, infection, high blood sugar and menstruation.

**Why is ACR important in diabetes?**
It is the earliest sign of diabetic kidney disease; yearly testing is recommended.


## Sources

- [KDIGO 2024 Clinical practice guideline for CKD](https://kdigo.org/guidelines/ckd-evaluation-and-management/)