Health

APRI Calculator

Estimate liver fibrosis using the AST to Platelet Ratio Index.

AST Level (IU/L)

AST Upper Limit of Normal (IU/L)

Platelet Count (10⁹/L)

APRI Score—

Significant Fibrosis (≥F2)—

Cirrhosis (F4)—

APRI = ((AST / AST_ULN) / Platelet count) × 100

What Is the APRI?

The AST to Platelet Ratio Index (APRI) is a simple, non-invasive marker used to predict significant liver fibrosis and cirrhosis, especially in patients with chronic hepatitis C.

Interpretation

< 0.5: Low probability of significant fibrosis.
0.5–1.5: Indeterminate — further testing may be needed.
> 1.5: Significant fibrosis likely.
> 2.0: Cirrhosis likely.