This is a PatientPlus article. PatientPlus articles are written for doctors and so the language can be technical. However, some people find that they add depth to the articles found in the other sections of this website which are written for non-medical people.

Spirometry Calculator

Post your experience

See also our record on Spirometry

Spirometry Calculator Age Sex Male Female Height (cm) Predicted FEV1 FVC FEV1/FVC Ratio PEFR

This calculator uses an algorithm derived from healthy adult lifetime nonsmokers in Australia.¹

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

---

Document references

1. Gore CJ, Crockett AJ, Pederson DG, et al; Spirometric standards for healthy adult lifetime nonsmokers in Australia. Eur Respir J. 1995 May;8(5):773-82. [abstract]

Acknowledgements

EMIS is grateful to Dr Huw Thomas for writing this article. The final copy has passed scrutiny by the independent Mentor GP reviewing team. ©EMIS 2009.
Document ID: 2797
Document Version: 21
Document Reference: bgp2357
Last Updated: 30 Jun 2009
Planned Review: 29 Jun 2014

Related pages in Patient UK

Your Experience (^ top of page)

Health Topic information leaflets related to this topic (^ top of page)

Diagrams related to this topic (^ top of page)

Support Groups related to this topic (^ top of page)

PatientPlus articles related to this topic (^ top of page)

UK guidelines related to this topic (^ top of page)

Links to other selected websites related to this topic (^ top of page)

Poems and stories related to this topic (^ top of page)

Videos related to this topic (^ top of page)

Patient UK Newspaper (^ top of page)

Recent related news items

All news by related topic

Related Products (^ top of page)

Medical equipment

Books

Other - Useful resources (^ top of page)