Lung Capacity Calculator — Predicted FVC & FEV1
Enter your age, height, and biological sex to see predicted normal values for FVC (Forced Vital Capacity) and FEV1 (Forced Expiratory Volume in 1 second) based on the widely used Quanjer 1993 ECSC/ERS spirometry reference equations.
Biological sex
years
cm
Forced Vital Capacity — total air you can forcefully exhale
- 1
Height in metres
170 ÷ 100 = 1.7 - 2
Predicted FVC (male)
5.76 × 1.7 − 0.026 × 35 − 4.34 = 4.54Quanjer 1993 male equation: FVC = 5.76·H − 0.026·A − 4.34 (H in metres).
How does this calculator work?
Using Quanjer 1993 ECSC/ERS equations, predicted FVC = 5.76·H − 0.026·A − 4.34 (males) or 4.43·H − 0.026·A − 2.89 (females), and predicted FEV1 = 4.30·H − 0.029·A − 2.49 (males) or 3.95·H − 0.025·A − 2.60 (females), where H is height in metres and A is age in years.
Formula
How this is calculated
Spirometry measures how much air you can breathe out forcefully. The two key values are FVC (the total volume of air exhaled in a forced breath, reflecting lung size) and FEV1 (the volume exhaled in the first second, reflecting airway flow). Their ratio, FEV1/FVC, is the primary indicator of obstructive lung disease: a ratio below about 70% suggests obstruction such as COPD or asthma.
This calculator uses the Quanjer 1993 European Community for Steel and Coal (ECSC/ERS) regression equations, which remain widely cited in textbooks and clinical practice. The equations predict FVC and FEV1 from height (in metres) and age (in years) separately for males and females, derived from population spirometry data. Height has the strongest positive effect; age has a negative effect (lung function declines gradually with age).
Note that these 1993 equations have been largely superseded by the GLI-2012 (Global Lung Initiative) multi-ethnic reference values in modern clinical laboratories, which also cover children and are specific to ethnicity. The values here are predicted normals for healthy adults aged 18–80 of European descent; they are useful for educational comparison but are not a substitute for clinical spirometry interpreted by a healthcare professional.
Frequently asked questions
FVC (Forced Vital Capacity) is the total volume of air you can forcibly exhale after a full breath in — it reflects overall lung size. FEV1 is how much of that air comes out in the first second — it reflects how open your airways are. Together their ratio (FEV1/FVC) diagnoses obstruction.
A ratio below 70% (or below the lower limit of normal for your age) suggests obstructive lung disease — conditions like COPD or asthma where the airways are narrowed and restrict airflow. A low FVC with a normal ratio can suggest a restrictive pattern. Diagnosis requires clinical spirometry and a doctor's assessment.
The Quanjer 1993 equations were derived from European adults and are a starting reference. Modern labs use GLI-2012 values, which account for ethnicity and extend to children and older adults. Always compare your measured spirometry results to the reference values used by your own lab.
Also known as
TG we-Calculate Editorial Team. (2026). Lung Capacity Calculator — Predicted FVC & FEV1 [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/lung-capacity-calculator
TG we-Calculate Editorial Team. "Lung Capacity Calculator — Predicted FVC & FEV1." TG we-Calculate. 2026. https://we-calculate.com/calculator/lung-capacity-calculator.
TG we-Calculate Editorial Team, "Lung Capacity Calculator — Predicted FVC & FEV1," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/lung-capacity-calculator
@misc{wecalculate_lung_capacity_calculator, title = {Lung Capacity Calculator — Predicted FVC & FEV1}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/lung-capacity-calculator}}, year = {2026}, note = {TG we-Calculate} }
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