Tuner
Free online guitar tuner and chromatic tuner for any instrument. Uses your microphone — works instantly in your browser, no app needed.
Ready to tune
Click below to grant microphone access. Your audio is processed locally and never leaves your device.
How to use the online guitar tuner
Click Start tuner, allow microphone access, then play one string at a time. The tuner detects the pitch and shows the nearest note, the cents deviation (how sharp or flat you are), and the exact frequency in Hz. Tune until the needle centres and the display reads 0 ¢. Use Chromatic mode for any instrument, or select Guitar, Bass, Uke or Violin to see the string reference panel with highlighted string detection.
Standard tuning reference
Standard guitar tuning from the thickest to thinnest string is E A D G B E. Bass guitar uses E A D G (B0 for 5-string). Ukulele standard tuning is G C E A. Violin uses G D A E.
About A4 reference frequency
Most modern music and orchestras tune to A4 = 440 Hz (ISO 16). Some orchestras and recording contexts use 441–444 Hz for a slightly brighter sound. 432 Hz is sometimes preferred by ear for its warmer quality. Use the Custom option to set any value between 400 and 480 Hz — useful for early music, period instruments or matching a specific ensemble.
What is a chromatic tuner?
A chromatic tuner detects any of the 12 notes of the Western scale (C, C♯, D, D♯, E, F, F♯, G, G♯, A, A♯, B) across all octaves. Unlike dedicated guitar tuners that only show standard EADGBE strings, a chromatic tuner works for any instrument in any tuning — drop D, open G, DADGAD and beyond. It shows the exact note, how many cents sharp or flat you are, and the precise frequency in Hz.
Frequently asked questions
Can I tune a ukulele with this tuner?
Yes. Select Uke mode to see the four standard strings (G4, C4, E4, A4) with auto-highlight. The tuner works for soprano, concert and tenor ukuleles in standard GCEA tuning, as well as any other ukulele tuning in Chromatic mode.
Can I tune a bass guitar?
Yes. Select Bass mode for 4-string (E1 A1 D2 G2) or 5-string bass (B0 E1 A1 D2 G2). The McLeod Pitch Method used by this tuner handles low bass frequencies accurately, down to B0 at around 30 Hz.
Does it work for violin, mandolin, cello or other instruments?
Yes. Select Violin mode for the G D A E string reference, or use Chromatic for mandolin, cello, trumpet, flute or any other instrument. The tuner detects any pitch from about 30 Hz to 5 000 Hz.
Can I use it for historical instruments or early music?
Yes. Use the Custom A4 button to set any reference pitch from 400 to 480 Hz. Baroque ensembles typically tune to A4 = 415 Hz; some Renaissance groups use even lower references. The tuner works for period lutes, viols, recorders and historical keyboards.
Can I tune in drop D, open G or other alternate tunings?
Yes. Use Chromatic mode — it shows any note, not just standard tuning strings. Tune each string to whatever target note your alternate tuning requires (for drop D, tune the low E string down to D2).
What does the cents reading mean?
Cents measure pitch deviation within a semitone — 100 cents equals one semitone. The needle swings left when you are flat (too low) and right when you are sharp (too high). Aim for the needle centred at 0 ¢. A difference of ±3 cents or less is inaudible to most listeners in a mix.
Does it work on iPhone, Android or tablet?
Yes. The tuner works in any modern browser — Safari on iPhone and iPad, Chrome on Android, and all desktop browsers. No download or app install is required. On iOS you may need to tap Allow when Safari asks for microphone permission.
Why is the tuner picking up the wrong note?
Background noise or nearby instruments can interfere with pitch detection. Try tuning in a quiet room, mute other strings with your hand, and play one string clearly. The adaptive noise gate filters most ambient sound, but loud environments will reduce accuracy. If the reading flickers, wait for the note to sustain and stabilise.
How accurate is the tuner?
Under normal conditions the tuner is accurate to ±1–2 cents. This uses the McLeod Pitch Method (MPM), which is more stable than basic autocorrelation — especially on the harmonic-rich tones of a guitar or bass. ±2 cents accuracy is well within professional tuning tolerance.
Is it free? Do I need to create an account?
Completely free, no account required. The tuner runs entirely in your browser using the Web Audio API and processes all audio locally on your device — no audio data is sent to any server.