Convert dB SPL into sound pressure using the reverse sound pressure level formula. Enter a decibel value and reference pressure to calculate sound pressure in pascals, millipascals, or micropascals.
dB SPL value:
Enter the decibel sound pressure level you want to convert.
Reference pressure:
The calculator uses a reference pressure, usually 20 µPa for air, as the base pressure.
Reverse formula:
The calculator finds the pressure ratio using 10 raised to the dB divided by 20, then multiplies by the reference pressure.
Converting dB SPL to sound pressure helps show the actual pressure change behind a decibel value. This can be useful for acoustics, audio testing, microphone calculations, sound measurement, engineering, and noise comparisons.
Sound pressure values are often very small, so dB SPL is easier to read. This calculator shows both the pressure ratio and the converted pressure value.
The reverse sound pressure level formula is:
p = p₀ × 10^(dB SPL ÷ 20)
Use the formula p = p₀ × 10^(dB SPL ÷ 20), where p₀ is the reference pressure.
Using the common air reference of 20 µPa, 60 dB SPL equals 0.02 pascals.
For sound in air, use 20 micropascals. For underwater acoustics, 1 micropascal is commonly used.
Yes. Sound pressure to dB uses dB SPL = 20 × log10(p ÷ p₀). dB to sound pressure reverses that equation.