A clean, accurate tuner for guitar, bass, ukulele, violin and more. Try it right here in your browser — no download, no signup, no nonsense.
Most tuner apps are bloated with paywalls, ads, and features you'll never use. iontuner does one thing well: tells you whether your instrument is in tune, accurately and instantly.
YIN-FFT autocorrelation, the same algorithm used in professional audio software. Locks onto the fundamental even through noisy environments and harmonic-rich plucks.
Every detection refined through octave-error correction and median smoothing. The needle stays still when you're in tune and only moves when you're not.
Guitar, bass, ukulele, violin, mandolin and chromatic. Every common alternate tuning — Drop D, DADGAD, Open G, Half Step Down, five-string bass — ready to go.
Audio is processed entirely in your browser or on your device. Nothing is recorded, nothing is uploaded, nothing leaves the page. Works offline once loaded.
Free on the web, free on iOS. No paywalls, no ads, no “upgrade to remove” nonsense. Tuners shouldn't have a monthly fee.
Pick your instrument. Play a string. Match the needle. That's it. No tutorial, no onboarding flow, no email signup. The way it should be.
And quite a few things without. Vocal warm-ups, brass, woodwinds — switch to chromatic mode and any sustained pitch will be detected.
Standard, Drop D, DADGAD, Open G, Half Step Down
4-string, 5-string, Drop D
Standard GCEA, Baritone DGBE
Standard GDAE
Standard GDAE
Detects any musical note
A native iOS app is in development — built with the same principles. No ads, no subscriptions, no compromises. Sign up below to know when it launches.