Lung Volumes and Capacities Calculator

Calculates IC, FRC, VC, and TLC from IRV, VT, ERV, and RV.

Inputs

Color mode links each input to the matching equation term and solving arithmetic.

Equation and Work

Equation:
Solving steps:
IC
—
mL
FRC
—
mL
VC
—
mL
TLC
—
mL
Normal/reference: Traditional adult example values: IRV 3100 mL, VT 500 mL, ERV 1200 mL, RV 1200 mL; IC 3600 mL, FRC 2400 mL, VC 4800 mL, TLC 6000 mL. Predicted values depend on age, sex, height, ethnicity, and smoking history.

Clinical Significance

IC, FRC, VC, and TLC from IRV, VT, ERV, and RV.

This calculator expands that idea by identifying the relevant measured values, substituting the selected inputs, and carrying the arithmetic through in the solving steps.

Used in pulmonary-function interpretation of restrictive and obstructive patterns.

Formal interpretation requires patient-specific predicted values and quality-controlled testing.

References (APA 7th Edition)

  1. Chang, D. W. (2020). Respiratory Care Calculations (Revised 4th ed.). Jones & Bartlett Learning. Formula content adapted from the uploaded text/reference packet.