Sound Level Meter

A phone microphone is not calibrated and compresses loud sound. The reading is trustworthy in the middle of the scale and reads low above about 100 dB. This is not a class-1 meter and will not serve for a measurement you have to show someone.

The instrument uses the phone's microphone and shows the value in dB.

• A large number, readable at arm's length.
• A chart of the last minutes — you can see it rise or fall.
• Minimum, average and maximum per session, reset with one button.
• A threshold with sound: an alert when the value goes above it.
• A table of everyday equivalents to compare your reading against.
• No ads. Under a megabyte. Works without internet.

The microphone is used only to measure the sound level. Nothing is recorded, stored or sent.

There is a voluntary support button in the instrument. It unlocks nothing and disables nothing: the app works exactly the same without it.

The app sends anonymous usage statistics; you can turn this off in settings.

Independent development: one person builds and maintains this app. A letter to xmaxxp@gmail.com is read by that person, not by a support desk.