01
Analyze Voice
Pitch, formants, intensity, and harmonicity measured from the signal and drawn over it. Values are validated against Praat's own routines.
Free and open-source · Browser and desktop
Phonetics software that runs in your browser
Phonia is a phonetics workstation for recording, annotating, and measuring speech, built to replace Praat for everyday research tasks. The analysis engine is written in Rust, compiled to WebAssembly for the browser build; a desktop build runs the same engine offline. Pitch, formant, and intensity measurements are checked against Praat under matched settings.
Capabilities
Record, measure, annotate, and plot.
02
Manage Audio
Import audio files or record from the microphone, and organize a corpus of recordings into projects with groups, tags, and search.
rec_2024-05-12.wav
interview_a3.wav
wordlist_deny.wav
03
Show Spectrograms
Formant and pitch tracks drawn over the signal, with a choice of built-in color scales or a custom gradient.
04
Annotate Recordings
Tiered intervals over the signal. Create boundaries by listening, nudge them by the sample, and export TextGrids.
05
Draw Plots
Pitch contours and formant tracks exported as SVG, PDF, TikZ, Typst, or Vega-Lite, or as plotting code for Python, R, and Julia.
Learning
Interface conventions
- Command palette (Ctrl/Cmd-K). Every action is listed with its shortcut, so nothing is buried two menus deep.
- One undo stack (Ctrl/Cmd-Z). Annotation edits and library changes — a renamed recording, a deleted tier — share the same history, so one shortcut reaches back through all of it.
- One selection. A range selected on the waveform is the same range on the spectrogram and in the tiers — playback, readouts, and export all use it.
Validation
Every measurement is checked against Praat.
Praat is the standard tool in phonetics research and teaching. Phonia's pitch, intensity, and formant measurements are compared against a Praat oracle under matched settings, each with a documented tolerance band. A continuous-integration job re-runs the comparison on every change; a measurement drifting past its tolerance fails the build.
Most formant checks agree exactly; the remaining residual traces to Praat's own unpublished sinc-interpolation window, and is recorded in the repository's validation notes. Voice-report measures — jitter, shimmer, and harmonicity — are checked on sustained-vowel cases.
| Measure | Praat routine | Status |
|---|---|---|
| Pitch (F0) | Sound: To Pitch (ac) | Validated |
| Formants F1–F3 | Sound: To Formant (burg) | Validated |
| Intensity | Sound: To Intensity | Validated |
| Harmonicity | Sound: To Harmonicity (ac) | Validated |
Routine names as they appear in Praat.
The application
This frame runs the live application.
The frame below loads the same build served at this site's root.
phonia — live
Open Phonia to see it live.
Open Phonia