Enter the albumin concentration from your urine test report
Enter the creatinine concentration from the same urine sample
Sex is used for clinical context notes. KDIGO 2024 uses the same ACR thresholds for both sexes.
Enter Your Lab Values
Enter your urine albumin and creatinine concentrations above to calculate your ACR and get KDIGO kidney health classification.
How to Use the ACR Calculator
Enter Your Urine Albumin Value
Find the albumin concentration on your urine test report. Select the matching unit from the dropdown — most US labs report in mg/dL, while international labs may use mg/L or µmol/L. The calculator automatically converts all units before computing the ratio.
Enter Your Urine Creatinine Value
Enter the creatinine concentration from the same urine sample and select the correct unit (mg/dL is most common in US labs; mmol/L or µmol/L are common in European and Australian labs). Both values must come from the same spot urine sample.
Review Your ACR and KDIGO Category
Your ACR is displayed in both mg/g (US standard) and mg/mmol (international standard), along with your KDIGO albuminuria category (A1, A2, or A3), a color-coded classification bar, and a plain-language clinical interpretation of what your result means.
Add eGFR for Full CKD Risk Staging
Expand the Advanced Options section and enter your eGFR (estimated glomerular filtration rate) if available. This generates the KDIGO 5-by-3 CKD risk heat map showing your combined Low, Moderately Increased, High, or Very High risk level across all GFR and albumin stage combinations.
Frequently Asked Questions
What is a normal ACR value?
A normal ACR is below 30 mg/g (below 3 mg/mmol), which corresponds to KDIGO albuminuria category A1 — normal to mildly increased. Healthy young adults typically show ACR values below 10 mg/g. Values between 10 and 30 mg/g are within the normal A1 range but are on the higher end, and may warrant monitoring in people with risk factors. An ACR of 30 mg/g or above signals moderately increased albuminuria (microalbuminuria, category A2), which is a sign of early kidney damage. A value above 300 mg/g indicates severely increased albuminuria (macroalbuminuria, category A3). Two confirmed abnormal results at least 3 months apart are needed to diagnose persistent albuminuria per KDIGO guidelines.
Is a spot urine ACR as accurate as a 24-hour urine test?
Yes. Research published in the British Medical Journal and endorsed by the National Kidney Foundation has demonstrated that a random spot urine ACR has equivalent diagnostic accuracy to a 24-hour urine albumin excretion measurement for detecting significant albuminuria. The creatinine correction in the ACR ratio accounts for urine dilution differences, which is what made 24-hour collections necessary in the past. Spot ACR testing is now the preferred standard of care in primary care, nephrology, endocrinology, and cardiology because it is far more convenient for patients and produces reliable results. The first morning urine sample is often preferred for slightly better consistency, but any random spot sample is clinically acceptable.
What can cause a temporarily elevated ACR that is not kidney disease?
Several factors can transiently elevate the ACR without reflecting true underlying kidney damage. The most common causes include urinary tract infection, fever or acute illness, vigorous exercise in the 24 hours before sample collection, significant dehydration, poorly controlled hypertension, decompensated heart failure, and menstrual blood contamination in women. For this reason, KDIGO guidelines require two abnormal ACR results taken at least 3 months apart to confirm persistent albuminuria before a diagnosis of CKD is made. If your first ACR is elevated, avoid strenuous exercise for 24 hours before the retest, ensure you are well-hydrated but not overhydrated, and collect the sample when you are not acutely ill or have a UTI.
How does the KDIGO heat map work and what does my combined risk mean?
The KDIGO CKD Risk Matrix is a 5-by-3 color-coded grid that combines two independent dimensions of kidney health: your GFR stage (G1 through G5, representing kidney function levels) and your albuminuria category (A1 through A3, representing kidney damage level). Low risk (green) corresponds to G1 or G2 GFR with A1 albuminuria. Moderately Increased risk (yellow) appears at G1–G2 with A2, or G3a with A1. High risk (orange) appears at G1–G2 with A3, G3a with A2, or G3b with A1. Very High risk (red) covers G3b with A2–A3, and all G4 and G5 combinations. Higher combined risk is associated with faster CKD progression and increased cardiovascular event risk. This matrix guides referral decisions and treatment intensity.
Who should get an ACR test and how often?
Annual ACR testing is recommended by KDIGO, the American Diabetes Association, and the National Kidney Foundation for all adults with diabetes (Type 1 or 2), hypertension (high blood pressure), established cardiovascular disease or heart failure, a family history of kidney disease or hereditary kidney conditions, BMI over 30, tobacco use, or age over 60. For people already diagnosed with CKD, ACR testing frequency depends on risk category: annual for Low risk, 1–2 times per year for Moderately Increased risk, 2–3 times per year for High risk, and 3 or more times per year for Very High risk. For healthy adults without risk factors, routine ACR screening is not universally recommended but may be offered at health checkups.
What treatments can reduce an elevated ACR?
The ACR can often be reduced with targeted treatment, particularly in early-stage kidney disease. Blood pressure control to a target below 130/80 mmHg using renin-angiotensin-aldosterone system (RAAS) blockers — specifically ACE inhibitors or ARBs — has strong evidence for reducing albuminuria and slowing CKD progression. In people with type 2 diabetes, SGLT-2 inhibitors (such as empagliflozin and dapagliflozin) and GLP-1 receptor agonists have demonstrated significant ACR reduction in clinical trials. Tight glycemic control in diabetes (target HbA1c below 7%) also reduces albuminuria. Dietary protein restriction, smoking cessation, and weight loss in obese patients may provide additional benefit. Always work with your nephrologist or primary care provider to determine the right treatment plan.