Enter the sound intensity (W/m^2) into the calculator to determine the sound intensity in decibels.

Decibel Formula

The following formula is used to calculate the total number of decibels from the sound intensity level.

B = 10 * log ( I / I0 )
  • Where B is the sound intensity decibels
  • I is the sound intensity (W/m^2)
  • I0 is the reference sound intensity (equal to 10-12 W/m^2 for ambient noise)

To calculate the decibels, multiply 10 by the logarithm of the ratio of the sound intensity to the reference sound intensity.

Decibel Definition

A decibel is a unit of measure that defines the intensity of a sound pressure wave.

Decibel Example

Calculating decibels is typically a process of converting a sound intensity in one unit to another. This can be seen through the formula above that converts W/m^2 into decibels. Since decibels are a measure of the difference of sound pressures, a reference sound pressure must be given.


What is a decibel?

A decibel is a unit of measure of the intensity of sound. It’s also a measure of the intensity of the power of an electrical signal.

What is a safe decibel level?

The human ear can safely endure levels of less than 80 dBA. Any louder and extended exposure will likely lead to ear damage.