Frequency Display

Frequency Display listens through your microphone and shows the main frequency of the sound around you, live, in hertz. It also shows the nearest musical note and a full spectrum from 20 Hz to 20 kHz.

USEFUL FOR
• Checking the pitch of a voice, a whistle or an instrument
• Finding the frequency of a hum, a buzz or a tone from a speaker
• Testing a tone generator, a speaker or a microphone
• Science and physics classes about sound

WHAT YOU SEE
• The frequency in Hz, in large numbers you can read from a distance
• The nearest musical note and how many cents sharp or flat it is, for example A4 +0¢
• A live spectrum on a logarithmic scale, with the main frequency marked
• A level meter, so you know when the sound is loud enough to measure

FINE-TUNE THE MEASUREMENT
• A4 reference pitch from 415 to 466 Hz (440 Hz by default)
• Minimum and maximum frequency to focus on the range you care about
• FFT size from 1024 to 16384 samples, with the resulting resolution shown in Hz
• Sample rate from 8 kHz to 48 kHz
• Silence threshold, pitch smoothing and how fast spectrum peaks fall
• Reset everything to the defaults with one tap

CHOOSE YOUR INPUT
• Pick the audio source, including an unprocessed (raw) source on devices that support it
• Use the built-in microphone, a wired headset, a USB microphone or a Bluetooth input

MAKE IT YOURS
• Light and dark themes, or follow the system
• Seven main colors, or your wallpaper colors on Android 12 and newer

PRIVATE BY DESIGN
• Sound is analyzed in memory on your device. It is never recorded, saved or uploaded
• No account or sign-in
• Measures without an internet connection

Frequency Display is free and shows a small banner ad.