Piano Tuner Online
Free online piano tuner with microphone pitch detection for A440, A415, A442, A432, and other piano tuning standards.
Piano Tunings
Choose from 6 popular piano tuning standards. Each tuning page includes a pre-configured tuner and information about when to use it.
How to Tune a Piano
Tuning your piano is essential for producing beautiful music. A standard piano has 88 keys spanning over seven octaves, from A0 (27.5 Hz) to C8 (4186 Hz). The standard reference pitch is A4 = 440 Hz, which is the universal concert pitch used worldwide.
Piano tuning uses equal temperament, where each octave is divided into 12 equally spaced semitones. Begin by tuning the A4 key to 440 Hz, then use this reference to tune the surrounding notes. A tuning lever is used to turn the tuning pins, adjusting the tension of each string to achieve the correct pitch.
How to Use This Piano Tuner Online
- Select your tuning standard from the dropdown menu. Standard A440 is selected by default.
- Click the microphone button and allow microphone access when prompted.
- Play a single note on your piano. The tuner will automatically detect the pitch.
- You can also tap a specific note button to tune to that note. The tuner will show how sharp or flat you are from the target pitch.
- Turn the tuning pin with a tuning lever until the indicator is centered and the status shows "In Tune."
- Repeat for each note until your piano is fully in tune.
Understanding Piano Tuning Standards
Standard A440 - The international standard tuning with A4 set to 440 Hz. This is the universal reference pitch used by virtually all modern pianos, orchestras, and instruments worldwide.
Baroque A415 - Historical baroque pitch with A4 at 415 Hz, approximately a half step below modern concert pitch. Used for historically informed performances of Bach, Handel, and other baroque composers.
Concert A442 - Slightly higher than standard, with A4 at 442 Hz. Commonly used by European orchestras, particularly in Germany and Austria, for a brighter, more brilliant tone quality.
Piano Tuner Online FAQ
Can I use this piano tuner online for free?
Yes. PianoTuner.io is a free online piano tuner that runs in your browser. Click the microphone button, allow mic access, and play one piano note at a time to see whether the pitch is sharp, flat, or in tune.
What pitch does a standard piano tuner use?
Standard piano tuning uses A4 = 440 Hz. This is the A440 reference pitch used by modern pianos, orchestras, digital keyboards, and most electronic tuners.
Can this tuner hear piano notes through my microphone?
Yes. The tuner listens through your device microphone and detects the closest piano note. It works best when you play one note at a time in a quiet room.
Is this a piano note tuner or a reference tone tool?
It is both. You can use microphone pitch detection to check notes on your piano, or select a note and tuning preset to hear and compare against a reference target.
Should I tune an acoustic piano myself?
This tool is useful for checking pitch and learning piano tuning targets. Adjusting acoustic piano tuning pins requires the right lever and care, so call a piano technician if you are not comfortable making physical adjustments.