Health

FEV1/FVC Ratio Calculator

Interpret spirometry for obstructive vs. restrictive patterns.

FEV1/FVC Ratio
Pattern
GOLD Stage (if obstructive)
Ratio <0.70: Obstructive. Normal ratio + low FVC: Restrictive. GOLD: I ≥80%, II 50–79%, III 30–49%, IV <30% predicted FEV1.