Ascites SAAG Calculator
Enter serum and ascitic fluid albumin levels to calculate the SAAG and classify the cause of ascites.
Lab Values
Enter albumin concentrations from the same collection period.
Normal range: 3.5 – 5.0 g/dL
Obtained from diagnostic paracentesis
Formula
SAAG = Serum Albumin − Ascitic Albumin
Cutoff: ≥ 1.1 g/dL = portal hypertension
Enter lab values and click Calculate
SAAG Result
SAAG
—
g/dL
—
—
Input Summary
Serum Albumin
—
Ascitic Albumin
—
Common Causes
Clinical Note: SAAG is a screening tool only. Always correlate with history, physical examination, and additional ascitic fluid analysis (cell count, culture, LDH, glucose, cytology).
Copied to clipboard
Summary
Enter serum and ascitic fluid albumin levels to calculate the SAAG and classify the cause of ascites.
How it works
- Enter the serum albumin concentration measured from a blood sample (g/dL).
- Enter the ascitic fluid albumin concentration from paracentesis analysis (g/dL).
- The calculator subtracts the ascitic albumin from the serum albumin to produce the SAAG.
- A SAAG ≥ 1.1 g/dL indicates portal hypertension with 97% accuracy.
- A SAAG < 1.1 g/dL suggests a non-portal cause of ascites.
- Review the differential diagnosis list provided for each result category.
Use cases
- Differentiate cirrhotic ascites from malignant or infectious ascites.
- Guide clinical workup for new-onset ascites in hospitalized patients.
- Support decision-making before initiating diuretic therapy.
- Confirm portal hypertension in patients with chronic liver disease.
- Evaluate ascites etiology when multiple causes are suspected.
- Assist medical students and residents in bedside clinical reasoning.
Frequently Asked Questions
Last updated: 2026-06-14 ·
Reviewed by Nham Vu