PTA & SII Calculator
Quantify speech audibility live during patient consultations. Compute three and four-frequency pure-tone averages and estimate Speech Intelligibility Index values instantly.
Live Calculation Panel
Input standard patient audiometric thresholds directly into the fields below to generate clinical averages and speech intelligibility estimations immediately.
Threshold Inputs
Calculated Metrics
Enter decibel hearing level thresholds at standard octave frequencies from 500 Hz to 4000 Hz to update calculations.
Real-time values computed in strict compliance with ANSI S3.5-1997 standards for speech intelligibility and pure-tone averages.
[ 500 Hz: 20 dB ] [ 1000 Hz: 25 dB ] [ 2000 Hz: 30 dB ] [ 4000 Hz: 40 dB ]
3-Freq PTA: 25.0 dB HL | 4-Freq PTA: 28.75 dB HL | Estimated SII: 0.72 (Speech banana audibility: 72%)
Methodology and Standards
Pure-Tone Average Formulas
The three-frequency PTA utilizes thresholds at 500, 1000, and 2000 Hz. The four-frequency formula includes 4000 Hz, providing a more comprehensive assessment of high-frequency hearing loss common in noise-induced cases.
Speech Intelligibility Index
The estimated SII calculation maps threshold values against standard speech energy distribution. This provides a decimal value between 0.0 and 1.0, representing the proportion of acoustic speech cues available to the patient.