About the Decibel Calculator

A free tool for converting between decibels and power or amplitude ratios.

What it is

This calculator converts between a decibel value and its underlying ratio, supporting both the power/intensity formula (10ยทlogโ‚โ‚€) and the amplitude/pressure formula (20ยทlogโ‚โ‚€), solving in either direction depending on which field you leave blank.

Features

Power and amplitude modes

Correct formula for either type of quantity.

Solve either direction

dB to ratio, or ratio to dB.

Step-by-step

See the exact formula applied to your numbers.

Instant, private

Runs entirely in your browser. No data is sent anywhere.

Ready to use it?

Free, no sign-up required.

Open the Decibel Calculator