A formant shifter moves the resonances of a voice, its tone and apparent size, without changing the notes. Record or open a voice below, slide the formants down for a bigger, darker voice or up for a smaller, brighter one, or raise the pitch without the chipmunk sound. Nothing is uploaded.
Shift the Formants of a Voice
Move the formants (the tone and "size" of a voice) and the pitch separately. Record or open a voice, shape it, compare, download.
Processed on your device, never uploaded. Up to 10 minutes (files up to 200 MB). Works best on one voice without music.
Start here: record your voice or open a voice file.
Voice:
Voice envelopebefore after harmonics (pitch)
The resonances of your voice appear here.
Formants are the peaks of this curve. The formant slider moves the curve; the pitch slider moves the harmonic lines.
Record or open a voice to hear it here.
0 = the tone of the original voice. Down = bigger, darker; up = smaller, brighter.
0 = the same notes. The speed and length always stay the same.
No change yet: pick a preset or move a slider.
More options mix, envelope detail, file format
Related tools
How to use the formant shifter
- Add a voice. Press Record your voice and allow the microphone, or open a file (MP3, WAV, M4A, OGG, FLAC). A solo voice without music works best.
- Pick a preset or move the sliders. Formant changes the tone, from −12 to +12 semitones. Pitch changes the notes and starts at 0.
- Compare. Press Play and switch between A: Before and B: After at the same moment. The envelope chart shows the resonance peaks moving; the amber lines are the harmonics.
- Download. MP3 or WAV, the same length as your recording. The file name records the settings, for example
voice_formant-3_pitch-2.mp3.
More options holds a dry/wet mix (blend in the original), the envelope detail and the file format.
What formants are, in plain words
Your vocal folds make a buzz with a basic frequency, the pitch, plus many harmonics above it. Your throat, mouth and lips then act like a set of filters: some frequency areas ring louder than others. Those resonance peaks are the formants. The first two, F1 and F2, decide which vowel you hear: an “ee” has a low F1 and a high F2, an “ah” has a high F1 and a low F2. A longer vocal tract puts every formant lower, which is why a large adult sounds “bigger” than a child singing the same note.
| Vowel | Men F1 / F2 (Hz) | Women F1 / F2 (Hz) | Children F1 / F2 (Hz) | Women vs men |
|---|---|---|---|---|
| “ee” (heed) | 270 / 2290 | 310 / 2790 | 370 / 3200 | +2.4 / +3.4 st |
| “ah” (hod) | 730 / 1090 | 850 / 1220 | 1030 / 1370 | +2.6 / +2 st |
| “oo” (who’d) | 300 / 870 | 370 / 950 | 430 / 1170 | +3.6 / +1.5 st |
Worked out from the table: women’s formants sit about 1.5 to 3.6 semitones above men’s, and children’s about 4.0 to 6.2 semitones above. So formant shifts of a few semitones stay within the range of real voices; larger shifts sound less human. How high someone sings is a separate matter; see vocal ranges.
Pitch vs formant: two different controls
Pitch is how fast the voice vibrates, so it sets the note and the spacing of the harmonics. Formants are the shape laid over those harmonics, so they set the tone. A tenor and a soprano can sing the same note with different formants; one person can sing many notes with the same formants. One semitone is a factor of 21/12 ≈ 1.059 (semitones explained), and both sliders use that same step.
| You move | What changes | What stays | Sounds like |
|---|---|---|---|
| Pitch only (formant 0) | The notes and the harmonic spacing | The resonances, so the vowels and the size of the voice | The same person singing higher or lower |
| Formant only (pitch 0) | The resonance peaks | The notes | A bigger or smaller person singing the same melody |
| Both by the same amount | Everything | Nothing | A tape played faster or slower: the chipmunk or slowed-down sound |
Why pitching a voice up sounds like a chipmunk
A plain pitch shift multiplies every frequency by the same factor, the formants included. At +5 semitones the resonances move up by 33 %, as if the vocal tract were a quarter shorter; at +12 they double, and the voice sounds like a cartoon. Pitching down does the opposite and gives the slow, “drunk giant” sound.
Formant correction fixes this by keeping the resonances where they were while the notes move: in this tool, move the pitch and leave the formant at 0 (the Chipmunk-free pitch up preset is +5 semitones with formant 0). In our test on a synthetic vowel, a plain +5 shift moved F1 from about 700 Hz to about 920 Hz, while with the formant kept it stayed within 1.1 % of the original. If you only want a vocal higher or lower with a natural tone, the voice pitch changer does exactly that with one control.
| Formant shift | Frequency factor | An “ah” F1 of 730 Hz becomes | Tends to sound |
|---|---|---|---|
| −12 | ×0.500 | 365 Hz | monster or giant, clearly processed |
| −6 | ×0.707 | 516 Hz | giant, a very large speaker |
| −3 | ×0.841 | 614 Hz | bigger, darker, more “chest” |
| −1 | ×0.944 | 689 Hz | slightly fuller |
| +1 | ×1.059 | 773 Hz | slightly lighter |
| +3 | ×1.189 | 868 Hz | smaller, brighter, younger-sounding |
| +6 | ×1.414 | 1032 Hz | child-like |
| +12 | ×2.000 | 1460 Hz | tiny cartoon voice, clearly processed |
What people use it for, and what it cannot do
- A deeper or bigger voice for narration, a game character or a video: Deeper (formant −3, pitch −2) or Giant (formant −6, pitch −7).
- A vocal in a new key without the chipmunk sound: move the pitch, keep the formant at 0. For a whole song with music, use the karaoke pitch changer instead.
- Doubles and backing vocals: a copy with formant ±1 to ±2 and the mix at 50 % sounds like a second singer. Use the semitone calculator to count harmony intervals.
- Voice experiments: hear how your voice would sound with a smaller or larger vocal tract, then check your real range with the vocal range test.
Limits, honestly: it is not a live voice changer (no Discord, OBS or calls), not AI voice cloning and not text to speech. It processes one voice at a time; on a song with instruments the whole mix changes tone. A formant shift alone does not make a convincing gender swap: pitch, breathiness and speaking style matter too. Beyond about ±6 semitones the result sounds clearly processed.
Formant shifting in Audacity, Ableton, Logic and free plugins
| Program | Where the formant control is |
|---|---|
| Audacity 3.x | No separate formant shift. When you change the pitch of a clip in the clip’s Pitch and Speed dialog, “Optimize for voice” keeps the formants; the older Change Pitch effect has no formant option. See how to change pitch in Audacity. |
| Ableton Live | Warp the clip with the Complex Pro mode: its Formants control sets how much of the original formants is kept when you transpose. |
| Logic Pro | The Vocal Transformer plug-in has separate Pitch and Formant controls; Flex Pitch can shift the formants of single notes. |
| Any DAW (VST/AU) | MAutoPitch by MeldaProduction is free and has a formant shift; Melodyne and Auto-Tune include formant tools too (see pitch correction software). |
Which tool should you use?
| You want | Use |
|---|---|
| Tone and pitch as two separate controls | This formant shifter |
| A voice higher or lower with one simple control | Vocal pitch changer |
| A song moved to another key for singing | Male to female key change chart, then the karaoke pitch changer |
| A sound effect where the tone should move with the pitch | Pitch shifter |
| The voice in a video changed | Video pitch changer |
Questions about formant shifting
What does a formant shifter do?
It moves the resonance peaks of a voice without moving its notes. Down makes the voice sound bigger and darker, up makes it smaller and brighter. The melody and the timing stay the same.
Is formant shifting the same as pitch shifting?
No. Pitch shifting changes the notes. A plain pitch shift also moves the formants, which causes the chipmunk sound; a formant shifter controls them separately.
How do I pitch up a voice without the chipmunk effect?
Keep the formants where they are. Here: raise the pitch slider and leave the formant at 0, or use the Chipmunk-free pitch up preset.
Can it make a male voice sound female?
Partly. Raising the pitch and the formants a few semitones moves a voice in that direction, but intonation and breathiness matter as much, so the result is rarely fully convincing.
Is there a free formant shifting plugin?
Yes. MAutoPitch by MeldaProduction is free and has a formant shift. Without installing anything, this page does the same job in the browser.
Is my voice uploaded?
No. The recording and the processing stay in your browser; nothing is sent to a server.
Tested: what we measured
- 9 files downloaded from the tool (synthetic vowel, 120 Hz, resonances 700 / 1,220 / 2,600 Hz) and measured: formant shifts put F1 and F2 within 1.3 % of the target, pitch-only shifts kept them within 1.1 %.
- Pitch within 0.1 cents of the target in every file; length identical, sample for sample.
- A 3-second microphone recording and a stereo 48 kHz MP3 export were checked the same way; the preview you hear equals the downloaded file.
Tested in Microsoft Edge on a desktop. Last updated 28 September 2026 by Mayer. More tools on the online pitch changer home page; how we test: how it works.