Enter the input voltage and the output voltage into the calculator to determine the decibel attenuation.

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## Attenuation Formula

The following formula is used to calculate the decibel attenuation.

dbv = 20* log(Vo / V in )

- Where dbv is the attenuation in decibels
- Vo is the output voltage
- V in is the input voltage

To calculate the attenuation, take the log of the output voltage over the input voltage, then multiply by 20.

## Attenuation Definition

Attenuation is defined as the reduction of power being supplied to a device caused by an attenuator.

## Attenuation Example

How to calculate an attenuation?

**First, determine the output voltage.**Measure the output voltage.

**Next, determine the input voltage.**Measure the input voltage.

**Finally, calculate the attenuation.**Calculate the attenuation using the formula above.

## FAQ

**What is attenuation?**

An attenuator is a two-port resistive network. It is used to reduce the power being supplied to a device. The attenuation is the size of this reduction in power expressed in decibels.

**What is attenuation in decibels?**

Attenuation is measure in decibels because attenuation is a unitless but very small number expressed in a logarithmic scale. Since decibels are also logarithmic and unitless, it helps analyze the small changes more easily.