This free online pitch detector shows the pitch of any sound in real time. Sing, hum or play one note into your microphone to see the note, octave, frequency in Hz and how many cents sharp or flat you are on a live pitch graph, or upload an MP3 or WAV file. Nothing is recorded or uploaded.
Pitch Detector
– Hz
Press Start, then sing or play one steady note
Shows which voices sing the note and which open strings match it.
Microphone off. Nothing is recorded or uploaded: sound is analysed in your browser.
Notes detected
- Notes you hold for a moment appear here.
Session
- Lowest
- –
- Highest
- –
- Range
- –
- In tune (±10¢)
- –
- Time
- 0:00
Notes in the file
| Time | Note | Hz | Cents | Length |
|---|
Settings
Recent sessions on this device
- Sessions are saved here when you press Stop or analyse a file.
Related Tools
- Note Finder
Name any note you hear: what note is this?
- Singing Note Detector
See what note you are singing, note by note.
- Voice Pitch Analyzer
Track your voice's pitch, stability and vibrato.
- Frequency Detector
Measure any sound's frequency in Hz.
- Chromatic Tuner
Tune any instrument to the nearest note.
- Vocal Range Test
Find your lowest and highest notes and voice type.
- Pitch Accuracy Test
Check if you sing sharp or flat on target notes.
- Pitch Matching Game
Train your ear by matching notes you hear.
How to Use the Pitch Detector
- Press Start and allow the microphone when your browser asks. The detector listens to the room for a moment to learn how loud the background is.
- Sing, hum or play one steady note for about a second. Chords and several voices at once can’t be read as a single pitch.
- Read the note and octave, the frequency in Hz and the tuning needle. The graph shows how your pitch moves over the last ten seconds, and the piano strip lights up the key you are on.
- Press Hold (or the H key) to freeze a reading. Every note you hold for a moment is added to Notes detected, and the session box shows your lowest and highest notes and how often you were in tune.
- To check a recording instead, open the Audio file tab and choose an MP3, WAV, M4A or OGG file.
- When you finish, press Stop: the session is saved under Recent sessions on this device. Save result image downloads a card with your note and stats, and Full screen gives you a bigger display for practice.
If the readings jump by an octave, open Settings and choose a range lock for your voice or instrument. You can also change the A4 reference (for example 442 Hz for many orchestras), switch between sharps and flats, and show notes for B♭, E♭ or F instruments.
How to Read Your Result
| You see | What it means |
|---|---|
| Note and octave (e.g. A4) | The nearest note in scientific pitch notation. Middle C is C4; A4 is the A above it. |
| Frequency (Hz) | How many times per second the sound vibrates. A4 is 440 Hz at standard tuning. |
| Cents | How far you are from that note. 100 cents make one semitone; within ±5 cents sounds in tune to most listeners. |
| Needle and colour | Green with a tick: in tune. Amber: slightly sharp or flat (6–15 cents). Red: far off. The text always says sharp or flat, so you don’t have to rely on colour. |
| Pitch graph | Your pitch over time on note lanes. A flat line is a steady note; a wave is vibrato; a slide shows how you reach a note. |
| Session | Lowest and highest notes, the range between them and the share of the time you were within ±10 cents. |
New to cents? The guide to cents in music tuning explains why a few cents matter to singers and players.
Pitch, Frequency and Notes Explained
Pitch is how high or low a sound seems; frequency is the physical measurement behind it, in hertz. A pitch detector measures the frequency of the lowest repeating pattern in the sound (the fundamental) and names the nearest note. In the standard tuning used for almost all Western music, A4 is fixed at 440 Hz and every other note follows the equal-temperament formula f = 440 × 2(n − 69) / 12, where n is the note number (69 is A4). Each octave doubles the frequency: A3 is 220 Hz, A5 is 880 Hz.
| Note | Frequency (A4 = 440 Hz) |
|---|---|
| C4 | 261.63 Hz |
| C♯/D♭4 | 277.18 Hz |
| D4 | 293.66 Hz |
| D♯/E♭4 | 311.13 Hz |
| E4 | 329.63 Hz |
| F4 | 349.23 Hz |
| F♯/G♭4 | 369.99 Hz |
| G4 | 392.00 Hz |
| G♯/A♭4 | 415.30 Hz |
| A4 | 440.00 Hz |
| A♯/B♭4 | 466.16 Hz |
| B4 | 493.88 Hz |
All other octaves, from the lowest piano notes to the highest, are in the full musical note frequency chart.
What Can You Use a Pitch Detector For?
- Singing practice: check whether you are on the note, hold it steady and see where your voice drifts sharp or flat.
- Instruments: check the pitch of any note on a guitar, violin, flute, trumpet or piano; the range lock and transposition settings handle low and transposing instruments.
- Ear training: sing a note, then press the same key on the piano strip to hear it and compare.
- Recordings and songs: upload a vocal or instrument track to see its melody as a list of notes with times. To find the key of a whole song, use the song key finder.
- Speaking voice: see the typical pitch of your speaking voice in Hz for voice training or speech practice.
How This Pitch Detector Works
Your browser records short frames of sound (about 85 milliseconds, updated many times a second) and the detector looks for the repeating period in each frame. It uses the McLeod pitch method: a normalised autocorrelation that compares the sound with shifted copies of itself and picks the first strong repeat, which is the fundamental. This is more reliable for voices than simply taking the loudest frequency in a spectrum, because in many voices and instruments a harmonic is louder than the fundamental.
The classic failure of pitch detection is the octave error: reading a note an octave too high or too low when the harmonics are strong. The detector guards against it in three ways: it accepts only clear, repeating frames, it smooths readings over a few frames and ignores single-frame octave jumps, and the range lock stops it from looking outside your voice or instrument. How this approach compares with the YIN algorithm is explained in autocorrelation vs YIN.
How Accurate Is It?
In our tests with steady tones from C2 (65 Hz) to C7 (2,093 Hz), including voice-like tones with a weak fundamental, 484 of 488 readings were within ±3 cents of the true pitch, and the rest within ±5 cents; with added background noise, 44 of 46 were within ±5 cents. Silence and pure noise gave no reading at all instead of a random note. How the tools on this site are built and checked is explained on the methodology page.
Real-world accuracy depends more on the sound than on the software:
- Use a quiet room and keep the phone or laptop 20–50 cm from your mouth or instrument.
- Sing or play one note at a time; chords, reverb and loud backing tracks blur the reading.
- Natural vibrato moves the needle; look at the graph, where a centred wave means you are in tune on average.
- If notes jump an octave, choose the range lock for your voice or instrument.
What Note Is That? Voices and Open Strings
Under every reading the detector tells you what the note is used for: which voice types normally sing it and which instrument string it matches when played open. A4, for example, is the tuning note (440 Hz), the A string of a violin and ukulele, and is in the range of most voices; E2 is the low E string of a guitar and only basses sing it comfortably.
| Voice type | Typical range | Frequencies |
|---|---|---|
| Soprano | C4–C6 | 262–1,047 Hz |
| Mezzo-soprano | A3–A5 | 220–880 Hz |
| Alto | F3–F5 | 175–698 Hz |
| Tenor | C3–C5 | 131–523 Hz |
| Baritone | A2–A4 | 110–440 Hz |
| Bass | E2–E4 | 82–330 Hz |
Standard Tuning Notes for Common Instruments
| Instrument | Open strings (low to high) | Frequencies (Hz) |
|---|---|---|
| Guitar | E2 · A2 · D3 · G3 · B3 · E4 | 82.41 · 110.00 · 146.83 · 196.00 · 246.94 · 329.63 |
| Bass guitar | E1 · A1 · D2 · G2 | 41.20 · 55.00 · 73.42 · 98.00 |
| Violin | G3 · D4 · A4 · E5 | 196.00 · 293.66 · 440.00 · 659.26 |
| Cello | C2 · G2 · D3 · A3 | 65.41 · 98.00 · 146.83 · 220.00 |
| Ukulele (standard) | G4 · C4 · E4 · A4 | 392.00 · 261.63 · 329.63 · 440.00 |
Play each open string and check that the detector shows the right note within ±5 cents. For a screen made for tuning one instrument, use our instrument tuners.
Detect the Pitch of an MP3 or Song
Switch to Audio file and choose a recording (MP3, WAV, M4A or OGG, up to 50 MB and 10 minutes). The file is decoded and analysed in your browser, then you get the pitch curve of the whole recording, a list of notes with their start times, lengths and cents, the range and the most used note. Press play to follow the pitch curve as the recording plays, or download everything as a CSV file. It works best on a single voice or instrument: isolated vocals, a solo melody or your own practice recording.
Microphone Not Working? Quick Fixes
- No permission prompt or “blocked”: click the lock or camera icon in the address bar, allow the microphone for this site, then press Start again.
- Nothing happens on iPhone: make sure Safari has microphone access in Settings and that no other app (a call or recorder) is using it.
- The reading jumps around: move closer, sing or play louder and steadier, or choose Noisy room in Settings.
- Wrong microphone: pick your headset or USB microphone in Settings → Microphone.
- Still nothing: use the Audio file tab to analyse a recording made with your phone’s voice recorder.
Free, Private and No App Needed
The pitch detector is free, with no sign-up and no limits. It runs in current versions of Chrome, Safari, Edge and Firefox on iPhone, Android, Mac, Windows and Chromebook, so there is nothing to install. Audio from your microphone or file is analysed on your device and is never recorded, stored or sent to a server. If you do prefer an app, see our comparison of pitch detection apps for iPhone and Android.
Frequently Asked Questions
What note am I singing?
Press Start and hold a steady note: the big letter and number show the note you are singing, and the needle shows whether you are sharp or flat.
Why does it show the wrong octave?
Strong harmonics can make a note look an octave higher or lower. Sing a little louder and steadier, and choose the range lock for your voice or instrument in Settings.
Can it find the pitch of a song?
Yes, if the melody is clear. Upload the file in the Audio file tab to get the notes and a pitch curve; songs with loud backing music are harder to read than isolated vocals.
How many cents off is in tune?
Within ±5 cents sounds in tune to most listeners; beyond about ±15 cents most people hear the note as sharp or flat.
Does it work for guitar and other instruments?
Yes. Choose the Guitar, Bass guitar, Violin or Ukulele range lock for steadier readings, and set the instrument key for trumpet, clarinet, saxophone or French horn.