AHI Calculator
Compute the Apnea-Hypopnea Index — the standard severity metric for obstructive sleep apnoea.
What is AHI?
The AHI counts how many breathing pauses (apneas, ≥ 10 s) and shallow-breath events (hypopneas with ≥ 30% reduction) occur per hour of sleep. It is the primary metric used by sleep physicians to grade obstructive sleep apnoea severity and decide treatment options including CPAP.
How is it calculated?
AHI = (apneas + hypopneas) / hours of sleep. Severity: < 5 normal, 5–15 mild, 15–30 moderate, ≥ 30 severe.
Frequently Asked Questions
- Is AHI from a home test reliable?
- Yes for moderate-to-severe cases; mild cases may need lab confirmation.
- Does CPAP fix high AHI?
- Usually drops it below 5 when used consistently.
- Can children have apnoea?
- Yes — paediatric AHI thresholds are stricter (≥ 1 = abnormal).