How do I convert dB to Pascals?

p = p_ref × 10^(SPL/20), where p_ref = 20 μPa (= 2×10⁻⁵ Pa), the threshold of hearing.

What is the reference pressure for dB SPL?

The reference sound pressure is 20 μPa (micropascals) or 2×10⁻⁵ Pa, corresponding to the approximate threshold of human hearing at 1 kHz.

A-weighting adjusts measured sound levels to approximate human hearing sensitivity. It reduces low ( 6 kHz) frequencies. dBA is the A-weighted unit.

0 dB SPL corresponds to a pressure of 20 μPa — the approximate threshold of human hearing. It is not silence, but the quietest sound most people can detect.

What is the pain threshold in dB?

The pain threshold is approximately 130–140 dB SPL, corresponding to about 63–200 Pa of sound pressure.

Free Engineering Tool #216

Sound Level Converter

Convert between dB SPL and sound pressure (Pa). Enter a value in any unit and get instant conversion with A-weighting reference.

SPL = 20·log₁₀(p/p₀)dB ↔ PaA-Weighting Ref

Results

Sound Pressure

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dB SPL

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Sound Pressure

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Sound Pressure Level

where p₀ = 20 μPa = 2 × 10⁻⁵ Pa (threshold of hearing)

Common Sound Levels

Level (dB)	Pressure (Pa)	Example
0	0.00002	Hearing threshold
30	0.00063	Quiet room
60	0.02	Normal conversation
85	0.36	Heavy traffic
94	1.0	1 Pascal reference
120	20.0	Pain threshold
140	200.0	Jet engine (close)

Sound Level Converter | dB ↔ Pa | SPL Calculator | Free Tool

Published by Nikolai Shelkovenko on February 15, 2026 February 15, 2026

Results

Sound Pressure Level

Common Sound Levels