Free online Pitch Recognizer
Instantly identify any musical note, detect its exact frequency in Hz, and see how in tune you are — in real time, directly in your browser.
Our pitch recognizer listens through your microphone and tells you exactly which note you are playing or singing, its precise frequency in Hz, and how many cents sharp or flat you are from perfect pitch. No app to download. No account needed. Just open the page, click Start, and play.
How to use the pitch recognizer
- Click "Start Pitch Recognizer". Grant microphone access when the browser asks. Your audio is processed locally — nothing is sent to any server.
- Play or sing a note. Bring your instrument close to the microphone or sing clearly. Adjust the sensitivity slider if the tool is not reacting.
- Read the result. The wheel stops on the detected note. You will see the note name (e.g. A4), its frequency (e.g. 440 Hz), and the cents deviation.
- Check the cents bar. Green means you are in tune. Orange means slightly sharp or flat. Red means significantly out of tune.
What the pitch recognizer shows you
Every time you play a note, the pitch recognizer displays three pieces of information simultaneously:
- The note name — displayed in standard notation (C, D, E, F, G, A, B) with its octave number (e.g. A4, G3, C5). Accidentals show both the sharp and flat name (e.g. C# / D♭).
- The frequency in Hz — the exact fundamental frequency detected, to one decimal place. Concert A is 440.0 Hz.
- The cents deviation — how many cents (hundredths of a semitone) you are above or below perfect pitch. A deviation of ±10 cents or less is considered in tune for most musical purposes.
The chromatic scale reference at the bottom of the tool highlights the detected note so you can quickly locate it across multiple octaves.
Who is the pitch recognizer for?
Musicians
Singers
Students
Audio techs
Works any instrument or voice
This online pitch recognizer works with any sound source that produces a clear fundamental frequency:
- Voice (singing or speaking)
- Guitar, electric guitar, and bass
- Piano and keyboards
- Violin, viola, cello, and double bass
- Wind instruments: flute, clarinet, trumpet, saxophone
- Ukulele, banjo, and mandolin
- Any instrument within the 40 Hz – 4,200 Hz range
For best results, play one note at a time in a reasonably quiet environment. Adjust the sensitivity slider to match your distance from the microphone. If you are using a mobile device, position it 20–40 cm from the instrument.
Tips for accurate pitch detection
- Reduce background noise as much as possible. Turn off fans, close windows, and mute notifications. Quiet environment
- Pitch recognition works on monophonic input. Chords and harmonics can confuse the algorithm. One note at a time
- If the tool is not reacting, slide the sensitivity control toward "High". If it is reacting to background noise, slide it toward "Low". Adjust sensitivity
- Hold the note for at least half a second. The stabilizer averages recent detections to give you a reliable result. Sustained notes
- For acoustic instruments, 20–40 cm from the sound hole or body gives the clearest signal. Microphone position
Frequently asked questions
What is a pitch recognizer?
A pitch recognizer is a tool that listens to a sound through your microphone and identifies the musical note and its exact frequency in Hz. It also shows how many cents sharp or flat you are from perfect pitch. Think of it as a real-time tuner that works with any instrument and your voice.
How does the online pitch recognizer work?
The tool uses your browser's microphone API and an autocorrelation algorithm to analyze the audio signal in real time. It identifies the fundamental frequency of the sound and matches it to the nearest note on the chromatic scale. All processing happens locally in your browser — no audio is ever sent to a server.
Does it work with guitar?
Yes. The pitch recognizer works well with guitar, bass, electric guitar, and other fretted instruments. Play one string at a time and hold the note. For acoustic guitar, position the microphone about 20–30 cm from the sound hole. Increase the sensitivity setting if the tool is slow to respond.
What is the difference between a pitch recognizer and a tuner?
A tuner is designed to tell you whether a specific string or note is in tune relative to a fixed reference (usually A = 440 Hz). A pitch recognizer identifies whatever note you are playing — it does not assume what note you intend to play. This makes it useful for ear training, transcription, and exploring frequencies across the full musical range.
Is this pitch recognizer free?
Yes, completely free. No account, no subscription, and no download required. The tool runs entirely in your browser using the Web Audio API.
Does it work on mobile?
Yes. The pitch recognizer works on iPhone, Android, and tablet browsers. For best results on mobile, use Chrome or Safari and position your device 20–40 cm from the instrument. If the tool is slow to react, increase the sensitivity setting.