Kidney Function Panel Updated Apr 17, 2026

Albumin/Creatinine Ratio (ACR)

Albumin/Creatinine Ratio (ACR) is a urine measurement that compares albumin to creatinine in the same sample. On an Albumin/Creatinine Ratio lab report, ACR helps show how much albumin is present relative to urine concentration. It is often used in a kidney panel and is commonly reviewed as part of routine lab tracking.

What Is Albumin/Creatinine Ratio (ACR)?

Albumin/Creatinine Ratio (ACR) is a urine lab value that compares the amount of albumin to the amount of creatinine in a single sample. On a lab report, ACR helps show how much albumin is present after adjusting for urine concentration, which makes the result easier to compare across samples. ACR on a blood test is a common search phrase, but ACR is usually measured in urine rather than blood. In a Kidney Panel, Albumin/Creatinine Ratio on a lab report is often listed as a marker of how concentrated the sample is and how much albumin is present relative to creatinine.

Why Is Albumin/Creatinine Ratio (ACR) Tested?

ACR, or Albumin/Creatinine Ratio, is commonly included in a Kidney Panel and related urine testing. It is measured in routine screening or follow-up contexts to give a standardized view of albumin relative to creatinine. An ACR test adds context to other lab values by showing how urine concentration may affect the result. Albumin/Creatinine Ratio on a lab report is especially useful because the ratio can be read more consistently than albumin alone.

Already have your Albumin/Creatinine Ratio results?

Upload your blood test to BloodSight and see what each result means in context.

Get Started

Albumin/Creatinine Ratio (ACR) Normal Range

Group Range Unit
Adult Male 0–30 mg/g
Adult Female 0–30 mg/g

Reference ranges may vary by laboratory and individual factors.

What Does High ACR Mean?

A high ACR means the albumin amount is larger relative to creatinine in the urine sample. In many labs, a normal Albumin/Creatinine Ratio is below about 30 mg/g, so values above that are often considered high ACR. A high ACR on a lab report can reflect a more concentrated sample, more albumin in the urine, or both. The exact meaning depends on the ACR test method and the rest of the Kidney Panel.

Associated factors

Dehydration — lower urine volume can concentrate albumin and creatinine differently, increasing the ACR ratio.
Recent exercise — temporary shifts in urine protein handling can raise ACR for a short time.
Urinary concentration — a very concentrated sample can make the ACR test result look higher.
Recent high-protein intake — diet can slightly influence urine composition and ratio readings.
Smoking — can be associated with changes in urine albumin levels and higher ACR.
Older age — age-related variation can make high ACR more common in some groups.
Female sex — sex-based differences in creatinine excretion can affect the ACR ratio.
Pregnancy — changes in blood flow and urine handling can alter the ACR test result.
Certain medications — some medicines can change urine albumin or creatinine handling and shift ACR.
High blood pressure readings — pressure-related changes in urine filtering can be associated with high ACR.

What Does Low ACR Mean?

A low ACR means the albumin amount is small relative to creatinine in the urine sample. A low ACR is usually within the normal Albumin/Creatinine Ratio reference range, especially when it is below about 30 mg/g in common lab reporting. Very low ACR values often reflect a sample with little albumin and typical urine concentration. A low ACR on a lab report is generally less concerning than a high ACR, but the full pattern matters more than one number.

Associated factors

High fluid intake — more dilute urine can reduce the measured ACR ratio.
Recent low protein intake — lower albumin-related output may contribute to a low ACR test result.
Higher muscle mass — more creatinine can lower the ratio and produce low ACR.
Male sex — greater creatinine output can make low ACR more common.
Younger age — creatinine and albumin handling can differ from later life.
Collection timing — first-morning vs later samples can shift the ACR result.
Lab method differences — assay and reporting differences can create small low ACR shifts.
Lower urine albumin — less albumin in the sample directly lowers the ratio.
Recent rest after exercise — recovery can bring a temporarily high ACR back toward low ACR or normal ACR levels.
Dietary salt changes — short-term changes in fluid balance can influence the ACR test result.

How Albumin/Creatinine Ratio (ACR) Relates to Other Values

ACR is often read with creatinine, because creatinine is the denominator in the ratio. In a Kidney Panel, Albumin/Creatinine Ratio may be viewed alongside blood urea nitrogen (BUN) and serum creatinine, which give a broader picture of how waste products are handled. If a report also includes hematocrit (Hct), red blood cell count (RBC), or mean corpuscular volume (MCV), those values describe the blood cells themselves rather than the urine ratio. Together, these markers help show whether the ACR test result fits the rest of the lab pattern.

What Factors Affect Albumin/Creatinine Ratio (ACR) Levels?

Age, sex, and muscle mass can all affect the ACR test because creatinine output is not the same in every person. Hydration changes urine concentration, so the same Albumin/Creatinine Ratio on a lab report can vary from one sample to another. Time of day, recent exercise, and recent diet can also shift the ACR result. Lab method and reporting units matter too, so the Albumin/Creatinine Ratio normal range should be read using the same unit shown on the report. In some settings, pregnancy and altitude can also influence the ACR result through changes in fluid balance and urine handling.

How It Is Tested

ACR is usually measured from a urine sample, not a blood draw, even though people often search for ACR on a blood test. The lab measures albumin and creatinine and reports the ratio, often in mg/g or mg/mmol depending on the laboratory. The ACR test is then listed on the report as a single calculated value.

How to Prepare

No fasting is usually required for an ACR test. A first-morning urine sample is often used because it can make the Albumin/Creatinine Ratio result more consistent.

Frequently Asked Questions

What is the normal range for Albumin/Creatinine Ratio?
A common Albumin/Creatinine Ratio normal range is below 30 mg/g, although reference intervals can vary by lab and unit. On an ACR test, the report should always be read using the lab’s own range. The same ACR result may be shown in mg/g or mg/mmol depending on the laboratory.
What does ACR stand for?
ACR stands for Albumin/Creatinine Ratio. In lab reporting, it describes the amount of albumin relative to creatinine in a urine sample. What does ACR mean on a report depends on the unit and the lab’s reference range.
What does a high Albumin/Creatinine Ratio mean on a lab report?
A high ACR means albumin is higher relative to creatinine in the sample. In many lab systems, values above about 30 mg/g are considered high ACR. The result may reflect urine concentration, collection timing, or other factors that influence the ACR test.
What does a low Albumin/Creatinine Ratio mean on a lab report?
A low ACR means the albumin amount is small compared with creatinine in the same urine sample. Low ACR is often within the normal Albumin/Creatinine Ratio normal range. It can also happen when urine is more concentrated in creatinine or more dilute in albumin.
Can hydration affect Albumin/Creatinine Ratio?
Yes, hydration can affect ACR because it changes urine concentration. More fluid intake can lower the measured ratio, while less fluid intake can make a high ACR look more pronounced. This is one reason the ACR test is often paired with creatinine.
What is the difference between Albumin/Creatinine Ratio and creatinine?
Albumin/Creatinine Ratio is a ratio, while creatinine is one of the two measurements used to calculate it. Creatinine by itself does not show the ACR test result; it only helps adjust for how concentrated the urine sample is. ACR on a lab report and creatinine can therefore tell different parts of the same story.
What unit is Albumin/Creatinine Ratio measured in?
ACR is commonly reported in mg/g or mg/mmol. Some labs may also show an Albumin/Creatinine Ratio result in other unit formats, depending on the test system. The unit is important because the normal Albumin/Creatinine Ratio range depends on it.
How much can Albumin/Creatinine Ratio change between tests?
ACR can change between tests because urine concentration, timing, and recent exercise can all affect the result. Small day-to-day shifts are common, especially when comparing a morning sample with a later sample. For that reason, the ACR test is often interpreted using the overall pattern rather than one number alone.
Is Albumin/Creatinine Ratio different for men and women?
ACR can differ between men and women because creatinine output is related in part to muscle mass. That can affect the ratio even when albumin is similar. Some labs use the same Albumin/Creatinine Ratio normal range for both groups, while others may note small unit-based differences.
Why is Albumin/Creatinine Ratio tested in a Kidney Panel?
ACR is included in a Kidney Panel because it gives a standardized view of albumin relative to creatinine. That makes the Albumin/Creatinine Ratio test easier to compare across samples than albumin alone. It is one piece of the broader panel rather than a standalone finding.

Disclaimer

This content is for informational and educational purposes only. It is not intended as medical advice, diagnosis, or treatment recommendation. Reference ranges may vary by laboratory. Always discuss your results with a qualified healthcare professional.

Related Tests

Creatinine Clearance CrCl

Creatinine Clearance (CrCl) is a lab value that shows how much creatinine is removed from the blood over a set time. On a lab report or blood test, CrCl helps summarize how efficiently the body clears this waste product using measured urine and blood values. It is often reviewed with a kidney panel and other routine labs to give a broader picture of filtration and fluid balance.

→
Uric Acid

Uric Acid is a blood measurement related to urate, a waste product from the breakdown of purines. On a Uric Acid on a blood test, the result helps describe how much urate is circulating in the blood at that moment. It is often listed on a kidney panel and is read alongside other lab values to give a broader view of blood chemistry.

→
Cystatin C

Cystatin C is a blood marker measured to estimate how well the kidneys are filtering and clearing small proteins from the bloodstream. On a Cystatin C on a blood test, the value is reported as a concentration and is often used with other lab values to give a broader picture of body chemistry. A Cystatin C test result can vary with age, muscle mass, and other factors, so the Cystatin C reference range depends on the lab method.

→
BUN/Creatinine Ratio

BUN/Creatinine Ratio is a calculated lab value that compares blood urea nitrogen (BUN) with creatinine. It is commonly shown on a kidney panel and helps describe how these two waste-related markers relate to each other on a blood test. A BUN/Creatinine Ratio on a lab report is read alongside the individual BUN and creatinine values for a fuller picture of blood chemistry.

→
Microalbumin

Microalbumin is a urine lab measurement that reflects a small amount of albumin in the sample. On a Microalbumin test, the result helps describe how much of this protein is present and whether it falls within the Microalbumin normal range. Microalbumin on a lab report is often reviewed with other kidney panel values to give a broader picture of urine protein handling.

→