A free program for Android, by keuwlsoft.

SPL Meter is a sound pressure level meter app. The app uses the microphone to measure the sound pressure level (SPL) and convert it to an equivalent decibel value. It is an indicator for the sound pressure level in decibels (dB).

It is also possible to convert the result to a logarithmic scale.

The range between the noise floor and saturation is from 20 dB to 100 dB.

It is possible to use the app with a variety of devices. However, the best results will be obtained using devices with a microphone.