OhMyCalc

Sound Pressure Level (SPL) Calculator

Calculate sound pressure level in decibels (dB SPL) from acoustic pressure in Pascals using the standard reference pressure.

How to Use the SPL Calculator

  1. Enter the RMS sound pressure in Pascals (Pa).
  2. Click Calculate to get the SPL in dB and a perception category.
  3. Use a calibrated microphone or sound level meter to measure sound pressure accurately.

使用例

計算式

SPL = 20 × log₁₀(p / p₀), where p is the RMS sound pressure (Pa) and p₀ = 20 × 10⁻⁶ Pa (threshold of hearing).

よくある質問

What is sound pressure level?
SPL is a logarithmic measure of the effective sound pressure relative to the threshold of human hearing (20 μPa). It is expressed in decibels (dB).
What dB level is dangerous to hearing?
Prolonged exposure above 85 dB can cause permanent hearing damage. Levels above 130 dB cause immediate pain; above 140 dB risk instant hearing loss.
Is this calculator free?
Yes, all OhMyCalc calculators are completely free to use.