Tuner You Can Practice With
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Most tuners tell you where you are. IntonationPro shows you where you need to go — and whether you got there.
While you play, a glowing point traces your pitch across the screen in real time, leaving a comet-like trail that records the last eight seconds of your playing. You see every correction, every drift, every vibrato — without touching your phone. Place it on your music stand and watch your intonation as it happens.
PRACTICE IN TUNE — NOT JUST TUNE UP
This is the gap no other tuner fills. Conventional tuners show a needle or a number. The moment you start playing a phrase, the needle is useless — it can't tell you whether your D was in tune throughout the bow, whether you arrived at the E from above or below, or whether your vibrato centered on the note.
IntonationPro shows all of this, continuously, in real time.
THE KEY CHANGES EVERYTHING
Select your key before you play. The background grid instantly adjusts: the target lines shift to show you exactly where each note should sit — not just in equal temperament, but in the tuning system you've chosen. Play a major third in C major with Just Intonation selected, and the target line for E drops 14 cents. That's where it belongs. Now you can see it.
THREE TUNING SYSTEMS
Equal Temperament — the standard 12-TET used worldwide.
Just Intonation — pure intervals as they occur in acoustics. The major third sits 14 cents below equal temperament. The fifth is 2 cents high. For the first time, your tuner knows the difference between a C major third and a G major third.
Pythagorean Tuning — built on pure fifths. Ideal for melodic playing, solo lines, and string ensemble work.
Switch systems instantly. The grid adjusts in real time.
FOR EVERY INSTRUMENT THAT MAKES A PITCH
Strings, winds, brass, voice — IntonationPro works with anything that produces a sustained tone. There are no instrument profiles to set up. Play, and it listens.
External microphone support for professional studio use.
COLOR TELLS THE STORY
Green: within 6 cents of your target — you're in tune for this key and this tuning system.
Orange: 6 to 18 cents off — you're close. Watch the trail and correct.
Red: more than 18 cents off, or a note outside your selected key.
The trail changes color in real time as you play, so you can see a correction happening — mid-phrase, mid-bow, mid-breath.
VIBRATO — VISIBLE AS IT SOUNDS
No separate vibrato meter. Your vibrato appears naturally as the oscillation of the point itself. Its speed, width, and centering are visible from across the room. Slow, wide, uncentered vibrato looks exactly as unstable as it sounds.
CONCERT PITCH
A = 415 Hz (Baroque) · 432 Hz · 440 Hz · 442 Hz · 443 Hz (Vienna Philharmonic standard)
YOUR DATA STAYS YOURS
All audio processing happens entirely on your device. Nothing is transmitted to any server. No account required. No login. No analytics collected. No subscription.
FROM VIENNA
IntonationPro was created by Daniel Auner — violinist, conductor, and professor based in Vienna. It was built to fill a gap that every serious musician knows: a tuner that doesn't just tell you whether you're in tune, but helps you practice getting there.
FREE · PREMIUM
Free: full access to all features for the first 5 minutes of every session. No ads. No data collected.
Premium: unlimited sessions. One purchase. No subscription. No expiry date.
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