๐Ÿ”Š Sound Level Converter

dB SPL
Sound pressure level85.0 dB SPL
Sound pressure0.35566 Pa

* Calculated relative to the standard hearing threshold reference (20 micropascals = 0 dB SPL).

Convert between a sound's physical pressure (in pascals) and its sound pressure level relative to human hearing (decibels, dB SPL). Uses a logarithmic calculation based on the standard hearing threshold reference (20 micropascals) โ€” useful for acoustics or noise-measurement studies.

How to use

  1. Choose a direction: "dB โ†’ Pa" or "Pa โ†’ dB".
  2. Enter the value you want to convert.
  3. The converted result is shown automatically.

FAQ

Why does decibel use a logarithm instead of a simple ratio?

Human hearing perceives loudness logarithmically relative to physical sound pressure. The decibel is a logarithmic scale designed to match how we actually perceive sound.

What's the 20 micropascal reference value?

It's based on the quietest sound pressure a healthy human ear can detect (the threshold of hearing), which is defined as 0 dB SPL.

Does this support A-weighting, like dB(A)?

No โ€” this tool only calculates plain sound pressure level (dB SPL) and doesn't apply frequency-weighting curves like A-weighting.