Stop or switch tones on the Tone tab without the app closing on you. Measure sound frequencies with your microphone.
Frequency Counter Hz Tuner combines guided instrument tuning with a microphone-based Hz meter, measurement history, tone tools, and an ultrasonic scanner. Use the new guided flow to tune a guitar or ukulele one string at a time, or open the meter when you want to inspect the dominant frequency in a sound.
GUIDED GUITAR AND UKULELE TUNING
Choose guitar or ukulele and work through the strings in order. The guide listens to each string separately. When fresh readings stay within ±5 cents long enough to meet the stability check, the Confirm button becomes available. Tap it to save that string as verified. Each confirmed string records the observed Hz value, cents offset, and verification time. If you stop before finishing, the app saves the partial session and can offer to continue it after relaunch.
INSTRUMENT TUNER
The tuner includes standard string targets for guitar, bass, ukulele, and violin. Adjust the A4 reference when your tuning setup calls for a different reference. Guided string-by-string sessions are available for guitar and ukulele; the other instrument targets remain available in the regular tuner.
DOMINANT FREQUENCY METER
Use the microphone to view the dominant frequency of a sound in Hz. Select Auto, Music, Motor, or Hum mode to match the kind of reading you want to inspect. The meter and tuner provide distinct views, so you can move between a general Hz reading and instrument-focused pitch information without leaving the app.
MEASUREMENT HISTORY
Keep up to 500 measurement records for later reference. Add a note to identify a sound or session, and mark useful records as favorites. The history screen makes it easier to return to selected readings instead of relying on memory or separate notes.
TONE AND SWEEP TOOLS
Generate sine, square, triangle, or sawtooth waves from 20 Hz to 20 kHz. Use a steady tone when you need one frequency, or use sweep mode to move through a range. These controls are grouped in the Tone screen and can support listening, instrument, and audio experiments.
ULTRASONIC SCANNER
Scan the 17–24 kHz band, view the detected peak and a source hint, and review the recent detection log. Microphone response differs by device, especially at high frequencies, so the scanner does not promise that every phone can cover the entire band.
A PRACTICAL MULTI-TOOL FOR SOUND
• Tune guitar or ukulele with a guided string sequence
• Continue a saved partial tuning session after relaunch
• Use standard targets for guitar, bass, ukulele, and violin
• Read dominant sound frequency in Hz through the microphone
• Choose Auto, Music, Motor, or Hum meter modes
• Keep measurement records with notes and favorites
• Generate four waveform types in tone or sweep mode
• Inspect peaks and recent events in the ultrasonic band
Microphone permission is required for listening features. Readings and high-frequency coverage depend on the microphone, device hardware, the sound source, and the surrounding environment. The app is designed as an audio measurement, listening, and instrument-tuning aid.
The app works for what I needed, works to test hair clipper rpms. But sometimes the ads get in the way and you can’t even remove them
Developer Response
Thanks — clipper RPM is a good use for this, and I appreciate the detail.On the ad: I tested it and the banner does open expanded over the readouts. There's a small collapse arrow at its top-right that shrinks it, but it reopens each session, so you'd be tapping it every time you measure. I'd rather not pretend that's a fix.If you meant you'd like a way to remove ads entirely, there isn't one today — that's fair feedback and I'm looking at it. Thanks for taking the time to write.
The first ad that came up led me to a scam
denisedelacerda
Tried to scam me
Developer Response
That should never have happened and I am sorry it was your first experience of the app. The ads come from Google's ad network rather than from us, but a scam creative is not acceptable and I am reporting it so it can be blocked. Thank you for flagging it - reports like yours are the only way these get caught.
Fixed a rare case where the app could close by itself when a tone was stopped or switched on the Tone tab or when the Reference tone on the Tuner tab was stopped. A looping tone is now brought to a full stop before the app lets go of it.
Version 1.0.49
The developer, Kyu-Hee Jang, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Used to Track You
The following data may be used to track you across apps and websites owned by other companies:
Identifiers
Usage Data
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
Identifiers
Usage Data
Diagnostics
Privacy practices may vary, for example, based on the features you use or your age. Learn More
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
Seller
Kyu-Hee Jang
Size
72 MB
Category
Utilities
Compatibility
Requires iOS 17.0 or later.
iPhone Requires iOS 17.0 or later.
Mac Requires macOS 12.0 or later and a Mac with Apple M1 chip or later.
