StringwiseGuitar Tuner

Ready
IN TUNE
— Hz
— ¢
Start Tuner

Pluck a string to begin.

E2 · A2 · D3 · G3 · B3 · E4
Standard tuning · 440 Hz reference

On iPhone: tap the Share icon, then "Add to Home Screen".

How to use this guitar tuner

  1. Tap Start Tuner and allow microphone access when your browser asks.
  2. Pluck one string at a time and let it ring out — avoid strumming multiple strings together.
  3. Watch the note name and the gauge: the needle leans left if you're flat, right if you're sharp.
  4. Tighten or loosen the tuning peg until the needle centers and the display reads "IN TUNE."
  5. Repeat for each of the six strings, low E through high E.

Standard guitar tuning: EADGBE frequencies

Standard tuning names each open string, from lowest to highest pitch, as E‑A‑D‑G‑B‑E. Each note corresponds to a specific frequency, measured in Hertz (Hz), referenced against concert pitch A4 = 440 Hz:

Open-string frequencies for standard 6‑string guitar tuning
StringNoteFrequency
6th (thickest)E282.41 Hz
5thA2110.00 Hz
4thD3146.83 Hz
3rdG3196.00 Hz
2ndB3246.94 Hz
1st (thinnest)E4329.63 Hz

Why tune with a pitch-detection tuner?

Tuning by ear takes practice, and a guitar that's even slightly out of tune will make chords sound muddy and bend your sense of pitch over time. A microphone-based tuner like this one measures the actual frequency of the note you're playing and shows how many cents sharp or flat it is, so you can tune precisely without relying on relative pitch alone — useful whether you're a beginner or you just want a quick, reliable check before a session.

Privacy

Your microphone audio never leaves your device. Stringwise analyzes sound locally in your browser using the Web Audio API to detect pitch. Audio is not recorded, stored, or uploaded to any server at any point.

Frequently asked questions

Is this guitar tuner free?

Yes. Stringwise is free to use in your browser, with no account, sign-up, or download required.

Why does the tuner need microphone access?

It listens to the pitch of the string you play so it can tell you whether it's flat, sharp, or in tune. Without microphone access it can't detect any sound.

Is my audio recorded or uploaded anywhere?

No. All audio is analyzed locally on your device using the Web Audio API. Nothing is recorded, stored, or sent to a server.

Can I use this tuner offline?

Yes — once you've installed it or visited it once, a service worker caches the app so it keeps working without an internet connection. Microphone access itself does not require a network connection.

What tuning does this support?

Standard tuning: E2, A2, D3, G3, B3, E4 (low to high), referenced to A4 = 440 Hz.

Does this work for other instruments?

The pitch detection works on any single sustained note, so it can help tune similarly-ranged instruments like a ukulele or mandolin, but the string reference buttons are set up for standard 6-string guitar.