About Vietnamese Tone Trainer

Vietnamese Tone Trainer coaches the six Vietnamese tones with live pitch feedback: the 6 tones on 18 common syllables, then 12 real two-syllable words covering the hard contrasts. Your microphone listens, your pitch curve is drawn over the target curve, and one named hint at a time tells you exactly what to fix.

How it works

• Your browser samples the microphone and measures your pitch with autocorrelation, a standard signal-processing method: it finds how often your voice waveform repeats. No model is downloaded, and no audio is sent anywhere.
• Calibrate first. Vietnamese tones differ by pitch LEVEL as well as shape. Press Set my voice range and slide from your lowest to your highest comfortable note. The app then measures every utterance against your own range: 1.0 means the top of your range, 0.0 the bottom. Recalibrate any time in Settings; your range is stored only on this device.
• For each syllable, the app compares your pitch contour to the target tone's level and shape: mid flat, mid rising, low falling, falling then rising, dipping then rising high, or short low falling. You are judged on level and shape, not on how high or low your voice is in absolute terms.
• Press Check my tone after saying the syllable. If the contour matches, you score. If not, you get one named hint, such as: Nga rises all the way high: yours stopped in the middle, which sounded like hoi. After the small dip, climb to the top.
• Hear the target plays the target shape as a gliding tone, placed inside your own calibrated range, so you can hear the shape before you say it.
• Tone pairs unlock at 50 points. The app splits your utterance at the gap between syllables and checks each half against its target tone.
• Pitch tracking approximates tones. Background noise, a quiet voice, a creaky voice, or a cold can confuse it. If a native speaker says your tones sound right, trust them over the app.
• Native-speaker review sought: we are seeking review of this app by native Vietnamese speakers and Vietnamese teachers, in parallel with its release. Review is not a gate: the app is live while review is sought, and corrections will be folded in as they arrive.

The six tones

• Tone 1, ngang, mid flat (33, no mark): sing one steady note in the middle of your range. Example: ma, ghost.
• Tone 2, sac, mid rising (35, acute): start in the middle and climb to near the top, sharp and tense. Example: má, cheek.
• Tone 3, huyen, low falling (21, grave): start low-mid and drop to the bottom, smooth and breathy, held for a full beat. Example: mà, but.
• Tone 4, hoi, falling then rising (313, hook): dip down low, then rise back up to the middle. Do not climb to the top: that would be nga. Example: mả, tomb.
• Tone 5, nga, dipping then rising high (3-5 with a break, tilde): dip slightly, then climb all the way to the top, with a creaky catch in the middle. Example: mã, horse.
• Tone 6, nang, short low falling (3-2 with a stop, dot below): drop fast from low-mid and cut it off short, with a quick stop, like a heavy thud. Example: mạ, rice seedling.

The same syllable with a different tone is a different word. That is why tones matter: say the wrong tone and you may say a different word entirely. The hard pairs are hoi vs nga (both dip, but nga ends high and hoi ends mid), sac vs nga (both rise, but nga dips first), and huyen vs nang (nearly the same pitch, different length); the practice words are chosen to drill exactly those contrasts.

Huyen vs nang: the length difference

Huyen and nang have nearly the same pitch contour: both fall from low-mid. What tells them apart is length and voice quality. Nang is short and clipped, cut off with a glottal stop; huyen is held smooth for a full beat, often with a breathy voice. This app grades the pitch contour, and when the pitch scores for huyen and nang are nearly tied it uses duration as the tiebreak: under about 0.7 seconds favours nang, over about 0.9 seconds favours huyen, and in between it says so honestly instead of guessing. In real speech, listen for the stop: nang ends abruptly, huyen rings out.

Learn more

These links open other websites in a new tab. Vietnamese Tone Trainer isn't affiliated with any of them and sends them nothing.

Privacy

• Your voice never leaves your device. It is analysed in your browser frame by frame and immediately discarded. Nothing is recorded, uploaded or shared.
• No accounts, ads, cookies, analytics or trackers. The app loads nothing from other websites: the code is served from this site, and a security policy blocks connections anywhere else.
• Stored on your device only: which items you've tried, your points, badges, practice days and settings, your calibrated voice range, and whether you've seen the welcome message, in your browser's local storage. Clear it any time in Settings → Clear progress, or with the Offline proof → Delete all my data button, or by clearing this site's data in your browser.
• Offline copy: after your first visit, your browser keeps a copy of the app so it works offline. Clearing site data removes it.
• The microphone is only on while you're practising or calibrating. It turns off when you go back to the tone list, press “Turn off”, or switch to another tab.
• Hosting: like any website, the server that delivers the app's files may keep standard technical logs (such as IP addresses) of those downloads. The app itself sends nothing.
• Reference links go to other websites, which have their own privacy policies.

Disclaimer

• Vietnamese Tone Trainer is a home practice tool, not a teacher, therapist or safety device. Everything runs on your device: no video, audio or images are sent anywhere. Feedback is automatic and can be wrong. For real instruction, learn from a qualified Vietnamese teacher or a native-speaker community, linked on the Resources page.
• Pitch tracking approximates tones. Regional variation exists: Southern speakers realise the tones differently from Northern speakers (in much of the South, hoi and nga sound alike), and the app's target shapes describe standard Northern (Hanoi) citation tones. Voice quality (breathy, creaky, glottal) is part of real tones and this app only measures pitch plus duration.
• The app is provided “as is”, without warranty of any kind.

Accessibility

• Everything works with a keyboard. Feedback is announced to screen readers, and animations follow your device's “reduce motion” setting. Sound and confetti can be turned off in Settings.
• The live check depends on a microphone and on speaking. If that doesn't work for you, the tone descriptions, spellings, glosses and reference links still work on their own, and the Hear the target button lets you hear each tone shape.

Credits

• Pitch detection: autocorrelation, implemented from scratch for this app (no third-party libraries).
• Tone shapes follow the standard Chao tone-number descriptions of the six Vietnamese tones.
• Reference links: Wikipedia, Michigan State University Open Books, linked, not embedded.
• Built with the on-device coach pattern from the Little Hands app, and the pitch engine of the Mandarin Tone Trainer and the Cantonese Tone Trainer.

Vietnamese Tone Trainer version 1.0.0