Enter Age, Height and Gender. To see Percent Prediced, you must enter observed FVC, FEV1, and PEFR values in the appropriate boxes.
Calculate Spirometric Reference Values.
Age Sex  
Height (cm)    
  Observed Values Predicted Values Percent Predicted
FEV1 (L)
PEFR (L/min)

Developed by: fittowork.net
Measurements made in Spirometry
Abbreviation Measurement Description
VC (SVC) Vital capacity (slow vital capacity) Maximal amount of air exhaled steadily from full inspiration to maximal expiration (not time-dependent). It should be >80% of predicted, reduced in restrictive disease.
FVC Forced vital capacity Volume of lungs from full inspiration to forced maximal expiration. It is reduced in restrictive disease, and in obstructive disease if air trapping occurs.
FEV1 Forced expiratory volume in one second Volume of air expelled in the first second of a forced expiration. Reduced in both obstructive and restrictive disease.
FEV1% (FER) Forced expiratory ratio (FEV1/FVC)x100 Percentage of FVC expelled in the first second of a forced expiration.
Normal in restrictive disease - reduced in obstructive disease.
FEF 25-75% Forced expiratory flow between 25-75% Average expiratory flow rate at the middle part of forced expiration. It is a more sensitive indication of what is happening in the middle/lower airways, but is not as reproducible as FEV1. Normal in restrictive disease.
PEFR Peak expiratory flow rate Maximum rate of airflow achieved during expiration.
Source: aafb.org