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Decibel Calculator

CCE Copy

Decibel calculator for performing arithmetic on sound levels

Decibels are logarithmic therefore the values are converted back to linear before performing any mathematical operations like addition, subtraction, multiplication and division.

Use the calculator to see this in action with the full formula provided with the result.

Decibel add and subtract + −

Enter the decibel values as you would with a standard calculator.

Decibel multiply and divide × ÷

Enter the decibel value first and then enter the factor to multiply or divide by second.

Calculate percentage of a decibel %

As with multiplication, enter the decibel value first and then enter the percentage value second.

Tips to use

  • The use of the keyboard numeric keypad is supported (ESC to clear).
  • Click entries under "Calculations" to reload the results
  • Copy your result to the clipboard with Copy