Albumin Globulin Ratio Calculator
This calculator works out your albumin to globulin (A/G) ratio from a standard blood test, a figure your doctor may check alongside liver function tests or serum protein electrophoresis when investigating liver disease, kidney disease, inflammation or immune disorders. You choose your reporting units, g/L for most New Zealand laboratories or g/dL for some international labs, then enter your serum albumin and total protein results exactly as they appear on your lab report. The calculator derives your globulin figure by subtracting albumin from total protein, then divides albumin by globulin to produce your A/G ratio. Results are shown alongside typical normal ranges for albumin, total protein and globulin, plus a calculation breakdown showing exactly how each figure was reached. An interpretation guide flags whether your ratio falls below 1.0 (a reversed ratio), between 1.0 and 1.1 (borderline low), within the normal 1.1 to 2.5 range, or above 2.5, with a plain-language verdict explaining what that might mean and common causes worth discussing with your doctor. Use it to make sense of a blood test result before an appointment, or to track how your ratio changes over time. This calculator is educational only, not a diagnostic tool, and reference ranges vary between laboratories, so always check your result against your own lab's stated range and discuss any abnormal reading with a registered health professional.
1. Your Blood Test Values
2. Derived Values
| Albumin | 35 to 50 g/L |
| Total protein | 60 to 80 g/L |
| Globulin | 20 to 35 g/L |
| A/G Ratio | 1.0 to 2.5 |
Calculation Breakdown
Interpretation Guide
What Is the Albumin Globulin Ratio?
The albumin globulin (A/G) ratio is the proportion of albumin to globulin in the blood. Both are classes of serum proteins measured as part of a total protein test or a comprehensive metabolic panel. Albumin is made by the liver and performs functions such as maintaining fluid pressure and transporting hormones and drugs. Globulins are a broader group including immune proteins (immunoglobulins) and enzymes.
A healthy adult has more albumin than globulin in the blood, giving an A/G ratio above 1.0. When the ratio falls below 1.0 or rises well above 2.5, it can indicate an underlying condition that warrants further investigation.
The Formula
Globulin is not usually reported directly by laboratories. It is calculated from two reported values:
Globulin = Total Protein − Albumin
A/G Ratio = Albumin ÷ Globulin
For example: if albumin is 42 g/L and total protein is 72 g/L, then globulin is 30 g/L and the A/G ratio is 42 ÷ 30 = 1.40.
Normal Range
| Measure | Typical Normal Range (g/L) | Typical Normal Range (g/dL) |
|---|---|---|
| Serum albumin | 35 to 50 g/L | 3.5 to 5.0 g/dL |
| Total protein | 60 to 80 g/L | 6.0 to 8.0 g/dL |
| Globulin (derived) | 20 to 35 g/L | 2.0 to 3.5 g/dL |
| A/G Ratio | 1.0 to 2.5 (no units) | |
Reference ranges vary slightly between laboratories. Always compare your result against your own lab's stated reference interval.
What Does a Low A/G Ratio Mean?
A low A/G ratio (below 1.0) is called a reversed A/G ratio. It usually means albumin is lower than expected, globulin is higher than expected, or both. Common causes include:
- Liver disease: cirrhosis, hepatitis, or liver failure can reduce albumin production.
- Kidney (nephrotic) syndrome: albumin is lost through damaged kidney filters.
- Malnutrition or malabsorption: inadequate protein intake reduces albumin levels.
- Chronic inflammation or autoimmune diseases: inflammatory cytokines suppress albumin and raise globulins.
- Multiple myeloma or other blood cancers: abnormal plasma cells produce excess immunoglobulins, raising globulin and lowering the ratio.
What Does a High A/G Ratio Mean?
A high A/G ratio (above 2.5) usually reflects low globulin, which is less common but can occur in:
- Immunodeficiency disorders where immunoglobulin production is low.
- Certain genetic conditions affecting globulin synthesis.
- Steroid or corticosteroid use, which can suppress immunoglobulin levels.
A mildly elevated ratio is often not clinically significant on its own.
Worked Example
A routine blood panel reports: albumin 42 g/L, total protein 72 g/L.
- Globulin = 72 − 42 = 30 g/L
- A/G Ratio = 42 ÷ 30 = 1.40
- Interpretation: within the normal range (1.0 to 2.5).
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Sources and method: Pagana KD, Pagana TJ. Mosby's Manual of Diagnostic and Laboratory Tests (6th ed.). Formula: A/G Ratio = Albumin / (Total Protein − Albumin). Reference ranges based on standard clinical biochemistry practice; individual laboratory ranges may differ.
This calculator is for educational purposes only and is not a substitute for professional medical advice. Reference ranges vary between laboratories and testing methods. Always discuss your blood test results with your doctor or a qualified health professional.