Choose one task
Use the same sentence or sustained vowel each time you compare results.
Voice steadiness measurement
Pitch Variation Test
Compare relative pitch variation during the same vowel or passage; use raw CV instead of a quality score.
CV = standard deviation ÷ mean × 100%. Lower values mean less pitch movement in this sample, not a better voice or medical stability.
100% client-side. Audio is never uploaded. Results are stored only when you choose Save.
Keep volume even
Sudden volume changes and vocal fry can reduce reliable pitch samples.
Compare like with like
Natural conversation should vary more than a sustained comfortable tone.
What is calculated?
CV = standard deviation ÷ mean × 100%. Lower values mean less pitch movement in this sample, not a better voice or medical stability.
Microphones, noise and octave errors affect results. Accuracy has not been independently validated. Pitch bands are interface descriptions, not population norms or diagnoses.
Method and interpretation
Use this result
Compare relative pitch variation during the same vowel or passage; use raw CV instead of a quality score.
Mean 100 Hz and SD 5 Hz produce CV 5%. Expressive conversation naturally varies more than a held vowel.
Read the measurement guideWhat is calculated?
Autocorrelation analyzes 2,048-sample frames about every 45 ms, within 60–400 Hz. Frames need RMS ≥ 0.01 and correlation ≥ 0.55. A result requires 20 detected frames and at least 20% detection coverage.
Median, mean and standard deviation use detected frames. Endpoints are the 2nd and 98th percentiles; trimming extremes does not guarantee removal of octave errors.
Microphones, noise and octave errors affect results. Accuracy has not been independently validated. Pitch bands are interface descriptions, not population norms or diagnoses.
These tools share one pitch detector; each page offers a different way to interpret its measurements.
Frequently asked questions
What is pitch stability?+
It describes how tightly detected pitch samples cluster around the average during a controlled speaking task.
Use this result+
Mean 100 Hz and SD 5 Hz produce CV 5%. Expressive conversation naturally varies more than a held vowel.
What is calculated?+
CV = standard deviation ÷ mean × 100%. Lower values mean less pitch movement in this sample, not a better voice or medical stability.
Can this diagnose a voice disorder?+
No. It is an informal acoustic measurement, not a clinical jitter or pathology assessment.