The pure-tone average hearing loss calculator gives the pure-tone average of each ear, the WHO grade of hearing loss, the weighted binaural average and the asymmetry from the thresholds of an audiogram at 500, 1000, 2000 and 4000 hertz.
How the calculation works
- Enter the thresholds of the right and left ear.
- Read the pure-tone average of each ear.
- Read the WHO grade, the binaural average and the difference.
Example
The right ear has thresholds of 25, 30, 35 and 45 dB HL, so a pure-tone average of 33.8 dB HL. The left ear has 20, 25, 30 and 40 dB HL, an average of 28.8 dB HL. The better ear is at 28.8 dB HL, which is WHO grade 1 (mild). The weighted binaural average is (5 × 28.8 + 33.8) / 6 = 29.6 dB HL, and the difference between the ears is 5.0 dB.
Why it matters
The calculator helps audiology and speech therapy students, hearing aid professionals, occupational health nurses and anyone who wants to understand an audiogram report.
Good to know
The pure-tone average describes the loss at the speech frequencies and does not capture the whole picture: the high-frequency loss typical of noise exposure and age is only partly represented, and the ability to understand speech in noise, which is measured by speech audiometry, can be much worse than the thresholds suggest. The grade is a statistical classification, not a diagnosis of the cause. Air and bone conduction thresholds must be compared to separate conductive from sensorineural loss, and a marked asymmetry requires medical evaluation. Adults and children use different scales, and the WHO grades here are for adults. Screening results must be confirmed by a full audiological assessment by a qualified professional.
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