Viola tuner
C, G, D and A, one open string at a time, with the sound kept on your device.
- Nothing is uploaded
- Works offline after first visit
- Open source
- Free, no account. The microphone is on only until you press Stop
Tune your viola to C, G, D and A with your microphone, or press a string button to hear its note and tune by ear. The tuner names the string you played and shows with a needle whether it is sharp or flat. It is free, and the sound from your microphone is not uploaded: everything runs in your browser on your device.
–
Play one string or note
– Hz
Done
Free, no ads. Support StayPut
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 viola’s four strings are a fifth apart: C3, G3, D4 and A4, from the thickest to the thinnest. The A is the first string and the C the fourth. Press Start the tuner, play one open string, and the tuner lights the string it is closest to and shows how far off it is.
A worked example: you bow the open A and the tuner shows A with the needle to the right and “11 cents sharp: tune down”. Turn the A peg a small amount, or the fine tuner if your viola has one, bow again, and stop when the needle sits in the shaded middle and the A button fills in. Tune the A first: the D, G and C are then set from it in fifths.
Bow a long, steady note on one string at a time, and let it sound for a moment before you adjust. The page takes the middle of its last five readings, so one scratchy stroke does not throw the needle. The lowest string takes a little longer to settle than the others, so give the C a second.
The four open strings
The frequencies use the usual reference, A4 = 440 Hz, in equal temperament. They are the same numbers the page shows as a tooltip on each string button.
- 4th string, C: C3, 130.81 Hz
- 3rd string, G: G3, 196.00 Hz
- 2nd string, D: D4, 293.66 Hz
- 1st string, A: A4, 440.00 Hz
What this page does not do
- It hears one note at a time. Double stops, or two strings sounding together, will confuse it, so bow one string and let the others rest.
- With Viola chosen, the needle measures the distance to the nearest open string. A fingered note therefore shows as a large error from some open string. To read the name of a fingered note, choose Chromatic.
- It does not check your intonation up the fingerboard or say where a finger should go.
- It listens through the microphone, so in a room of players it hears all of them. Tune somewhere quiet or away from the group.
How it works
- Press Start the tuner and allow the microphone. Viola is already chosen.
- Bow one open string, a long note, and let it sound. The nearest of C, G, D and A lights up and the needle shows sharp or flat.
- Turn the peg or fine tuner until it says In tune, then tune the next string: A, D, G, C.
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
Which string do I tune first?
The A, then D, G and C. Each string is a fifth from its neighbour, so once the A is right the others can be checked against it by ear: bow two neighbouring strings together, and a fifth with no slow wobble in it is in tune. Then let the tuner confirm each one.
Is a viola tuned like a violin?
The viola’s G, D and A are the violin’s G3, D4 and A4. The viola’s lowest string is a C3, a fifth below the G, and it has no E string. The violin tuner has the violin’s G, D, A and E.
Can I tune to A 442?
Yes. Change the Reference pitch field; it takes values from 415 to 466. The string buttons and the needle both move to the new pitch. A number outside that range is ignored and 440 is used.
How do I tune without the microphone?
Press the A button to hear the note for two seconds, and tune your A string until the two sound as one and the slow wobble between them stops. Then tune D to A, G to D and C to G by bowing the pair together.
Is the sound from my microphone recorded or uploaded?
No. The pitch is measured by code running in this tab, about twenty times a second, and no sound is recorded or stored: only the last few pitch readings are held in memory while the tuner listens. Press Stop using the microphone to turn it off. Like any website, the host sees your connection’s IP address when the page loads, and the site counts visits with anonymous usage events that never include sound; the privacy page lists them field by field.
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.
Metronome
A steady click at any tempo, with the bar, the subdivisions and tap tempo, running on your device.
Blur faces in video
Faces found and covered frame by frame, on your own device, for children, bystanders and anyone who did not agree to be filmed. Always watch the result before you share it.
Remove silence
Shorter recordings without the dead air, made on your own device. Interviews and lectures stay private.