Online Guitar Tuner
Use your microphone to tune your guitar in real time with standard, drop, and custom tunings
- Click Start Tuner and allow microphone access when your browser asks.
- Select a Tuning Preset such as Standard (E A D G B E), Drop D, Drop C, DADGAD, or Whole Step Down.
- Choose the string you want to tune from the string buttons (6th to 1st).
- Pluck the string and watch the detected frequency, cents, and tuning dots update in real time.
- Adjust the tuning peg until the center dot is highlighted and the string is in tune.
This tuner supports multiple built-in tunings so you can move beyond standard tuning without extra apps:
- Standard (E A D G B E)
- Drop D, Drop C, Drop B, Drop A
- Half Step Down and Whole Step Down
- DADGAD and popular open tunings like Open D and Open G
- Custom Tuning mode, where you can assign any note to each string
- Use a quiet room so your microphone picks up only your guitar.
- Hold the guitar close to your device or point the microphone toward the sound hole or pickups.
- Pluck one string at a time and let it ring out while the tuner detects the pitch.
- If the reading jumps around, pluck a little softer and closer to the middle of the string.
The guitar tuner processes audio entirely in your browser using Web Audio. Your microphone signal is not uploaded or stored on any server, which makes this tuner safe to use for practice, rehearsal, and live setups.
Want more browser based tools? Explore other free utilities on the LeanTul tools page.
How do I allow the tuner to use my microphone?
Click the Start Tuner button and your browser will prompt you to allow microphone access. Choose the correct input device and select Allow so the tuner can detect your guitar's pitch.
Is this guitar tuner accurate enough for real playing?
Yes. The tuner provides real-time pitch detection with frequency and cents readouts, which is accurate enough for practice, recording prep, and live use when your microphone is set up correctly.
Which tunings are supported?
The tuner supports Standard, Drop D, Drop C, Drop B, Drop A, Half Step Down, Whole Step Down, DADGAD, Open D, Open G, and a Custom Tuning mode where you can define your own notes.
Does my audio get uploaded anywhere?
No. All processing happens in your browser. The microphone signal is analyzed locally and is never sent to LeanTul servers.
Can I use this tuner on my phone or tablet?
Yes. As long as your device has a microphone and a modern browser, you can open this page and use the tuner on mobile, tablet, or desktop.
Can I tune other instruments?
The tuner is designed around 6-string guitar tunings, but because it uses chromatic pitch detection, you can use it as a general tuner for other stringed instruments if you know the target notes.