Ukulele tuner
G, C, E, A, one string at a time, with the sound kept on your device.
- Nothing is uploaded
- Works offline after first visit
- Open source
- No watermark · limit is your device’s memory; phones hold less
Tune a soprano, concert or tenor ukulele online to G C E A with your microphone, or by ear with reference notes. It is free, and the sound from your microphone is not uploaded: everything runs in your browser on your device. Your browser asks for microphone permission, and after one visit and a short wait the page works offline.
–
Play one string or note
– Hz
Done
Open the network tab. Your files never appear in it.
Add files and run the tool to see every request this tab makes.
Your files are processed on this device and never sent to a server. Reload the page to clear everything from memory.
A soprano, concert or tenor ukulele is tuned G4, C4, E4, A4, reading from the string nearest your chin to the one nearest the floor. It is a re-entrant tuning: the G string is higher than the C next to it, which gives the ukulele its bright, close chords. Many people remember it as “My Dog Has Fleas”.
A worked example: you pluck the second string and the tuner shows C with “23 cents sharp: tune down”. Loosen the peg past the note, then bring it slowly back up until the needle rests in the shaded middle and the C button fills in. Nylon strings stretch a lot when they are new, so a fresh set can need tuning every few minutes for the first day.
If your uke has a low G string (a thicker G tuned an octave below, G3), choose Ukulele, low G, so the tuner aims that string at G3 rather than G4 and does not mistake it for a flat C. A baritone ukulele is tuned like the top four strings of a guitar, D3 G3 B3 E4; use the Chromatic setting for it.
No microphone, or a noisy room? Press G, C, E or A to hear each note for two seconds, then tune your string until the two sound as one and the slow wobble between them stops.
How it works
- Press Start the tuner and allow the microphone. Ukulele is already chosen.
- Pluck one string and let it ring. The nearest of G, C, E and A lights up.
- Turn the peg until it says In tune, then tune the next string.
In your browser, not on a server
Your browser opens the microphone (getUserMedia) with its noise suppression and automatic gain turned off, and the Web Audio API hands this page about 85 ms of sound twenty times a second. Each slice is compared with delayed copies of itself (the McLeod pitch method) to find the period of the note, which gives its frequency to a fraction of a hertz; the reading is then dropped. The string buttons play a tone from a Web Audio oscillator.
Compared with upload-based tools: Tuner apps ask for an install and access to much more than the microphone, and many tuner websites are buried in ads and trackers. Here the sound goes from your microphone to this tab and nowhere else, and nothing is kept.
Verify it yourself. Give the page a short while after one visit to save itself for offline use, then turn off Wi-Fi or switch to airplane mode and run the tool again. Or open your browser's developer tools (F12, or Cmd-Option-I on a Mac), pick the Network tab, and watch it while you convert. The panel above does the same count for you.
Questions
Soprano, concert and tenor: is the tuning the same?
Yes, all three use G C E A. Only the baritone differs (D G B E), and for that choose Chromatic.
My ukulele goes out of tune after a few minutes. Is the tuner wrong?
Almost certainly not: new nylon or fluorocarbon strings keep stretching for a day or two. Tune, gently pull each string away from the fretboard, and tune again. Warmth from your hands and the room also moves the pitch a little.
Does it work with low G tuning?
Yes. Choose Ukulele, low G from the list: the G button then plays and aims for G3, an octave below the usual G4, and the other three strings stay the same.
Can I tune it to a different key, like D6 (A D F♯ B)?
Choose Chromatic and bring each string up a whole step: G to A, C to D, E to F♯ and A to B. The big letter shows each note as you go.
Is the file uploaded anywhere?
No. There is no server in this process. The page is a static file and the work is done by code running inside your browser tab. Give the page a short while after one visit to save itself for offline use; then you can turn off Wi-Fi and it still works.
More video and audio tools
Online tuner
Play a note and see how sharp or flat it is. Guitar, bass, ukulele, violin or chromatic, with the sound kept in your tab.
Mic test
Check that your microphone works before a Zoom, Teams or Discord call: speak and watch the level, then play back five seconds to hear how you sound. Nothing is uploaded.
Webcam test
Check that your webcam works before a Zoom, Teams or interview call: see the live picture, the real resolution and the measured frame rate. Nothing is uploaded.
Audio to video
Put a song, a podcast episode or a voice note on a still picture, ready for YouTube or social apps. Made on this device.