Pitch Detector & Note Finder
Wondering what note you're singing? Just hum, sing, or play into your mic — this tool instantly tells you. See the note name, Indian swar, frequency in Hz, octave, and how sharp or flat you are. All processing happens in your browser — your audio never leaves your device.
Pitch History
✅ How to Use the Pitch Detector
- Click Start Listening and allow microphone access when prompted.
- Sing, hum, whistle, or play a single note on any instrument.
- The large display shows your note name, Indian swar, and exact frequency.
- The tuner needle shows whether you are sharp (right) or flat (left) of the note.
- The pitch history graph tracks your pitch over time — useful for seeing drift.
- Use the A4 = selector to switch between 440 Hz (standard) and 432 Hz tuning.
How It Works
The pitch detector uses your browser's Web Audio API to capture microphone input, then applies an autocorrelation algorithm — the same technique used by professional hardware tuners — to find the fundamental frequency of your voice or instrument. Autocorrelation works by comparing a signal against a time-shifted copy of itself: the shift at which they match most closely corresponds to the period of the fundamental pitch. The detected frequency is then converted to a MIDI note number and matched to the nearest semitone, with the remaining deviation shown in cents (100 cents = 1 semitone). All audio processing runs locally in your browser — no audio is ever uploaded or stored.
Frequently Asked Questions
How accurate is the pitch detection?
Very accurate for sustained single notes — typically within ±1–2 cents. Accuracy is best with singing, humming, or whistling in a quiet room. Background noise or very short notes reduce accuracy.
Does it upload my audio to a server?
No. All pitch detection runs in your browser using the Web Audio API and JavaScript. No audio data is ever sent to any server, stored, or transmitted.
What is "cents deviation"?
A cent is 1/100th of a semitone. If you are singing A4 (440 Hz) but the meter shows +20 cents, you are 20 cents sharp — slightly above the note. −50 cents means you are exactly halfway between two notes.
Can it detect chords or multiple notes at once?
No — pitch detection is inherently monophonic. It finds the single dominant frequency in the signal. For chords or polyphonic instruments, only the strongest frequency is shown.
How are Indian swar names mapped?
The mapping is relative to C as Sa. C = Sa, D = Re, E = Ga, F = Ma, G = Pa, A = Dha, B = Ni. Sharps and flats are shown as komal (flat) or tivra (sharp) variants. This matches standard Hindustani swar notation.
Why does the note flicker between two values?
If your pitch is close to the boundary between two notes (near ±50 cents), the detector may alternate between them. Steady, sustained notes produce stable readings. The needle shows exactly where you sit between notes.
Can I use a different reference pitch than 440 Hz?
Yes — use the A4 selector at the top to switch between 432 Hz, 440 Hz, and 444 Hz. Some orchestras and Indian classical musicians prefer slightly different reference pitches.
Swar Reference — C as Sa
| Western Note | Indian Swar | Full Name | Type |
|---|---|---|---|
| C | Sa | Shadja | Shuddha |
| C# / D♭ | Re♭ | Komal Rishab | Komal |
| D | Re | Rishab | Shuddha |
| D# / E♭ | Ga♭ | Komal Gandhar | Komal |
| E | Ga | Gandhar | Shuddha |
| F | Ma | Madhyam | Shuddha |
| F# / G♭ | Ma♯ | Tivra Madhyam | Tivra |
| G | Pa | Pancham | Shuddha |
| G# / A♭ | Dha♭ | Komal Dhaivat | Komal |
| A | Dha | Dhaivat | Shuddha |
| A# / B♭ | Ni♭ | Komal Nishad | Komal |
| B | Ni | Nishad | Shuddha |
References & Notes
- Pitch detection uses the autocorrelation method — same algorithm as professional hardware tuners
- Standard reference: A4 = 440 Hz (ISO 16)
- Indian swar mapping: C = Sa (relative, not fixed pitch)
- All audio processing is client-side — no data leaves your browser
This tool is for musical reference. Accuracy depends on microphone quality and ambient noise.