Check a piano by sampling keys across the keyboard
Begin near the middle, then test notes in alternating lower and higher registers. This page reports individual pitches; it does not claim to replace a professional temperament or unison service.
Separate pitch measurement from full piano tuning
A piano key may drive more than one string, and those unisons can beat even when the large note name looks correct. The browser can reveal a drifting single key, while pin control, stretch, and unison work remain mechanical tasks.
Use attack, sustain, and room calibration deliberately
Strike one key, ignore the noisy first instant, and watch the sustained portion. If room noise keeps producing notes, calibrate in silence and close the sustain pedal so neighboring strings do not continue ringing.
Questions
These answers define what the browser reading can and cannot establish.
Can it tune the whole piano automatically?
No. It measures the sound arriving at the microphone one note at a time and never turns a tuning pin.
Why can one key produce a moving reading?
Multiple strings, room reflections, and the percussive attack can compete. Let the note settle and repeat it consistently.
What reference does the display use?
The shared engine maps equal-tempered note names around A4 at 440 Hz.
Sources used for the pitch model
The equal-temperament description and A reference follow published digital-piano documentation; browser microphone behavior comes from this site’s tested local pitch engine.
Live microphone or selected-file audio is processed locally in this browser and is not uploaded.