Authoritative definitions of the International System of Units and SI prefixes.
Unit conversion
Decibels sound-pressure level to Pascals Converter
1 dB SPL ≈ 0.000022440369086 Pa. Enter a value to convert dB SPL to Pa, then use the formula and table below. Displayed digits may be rounded.
Light & sound unitsInstant result
Decimals
Formula result = 0.00002 × 10^(input ÷ 20) ÷ 1. 1 dB SPL ≈ 2.24404e-5 Pa
Nonzero results too small for the selected decimal places use scientific notation.
Nonzero results too small for the selected decimal places use scientific notation.
Common examples
One value, several units
Pascals2.24404e-5 Pa
Millipascals0.0224 mPa
Conversion table
| dB SPL | Pa |
|---|---|
| 1 dB SPL | 2.24404e-5 Pa |
| 2 dB SPL | 2.51785e-5 Pa |
| 5 dB SPL | 3.55656e-5 Pa |
| 10 dB SPL | 0.0001 Pa |
| 25 dB SPL | 0.0004 Pa |
| 50 dB SPL | 0.0063 Pa |
| 100 dB SPL | 2 Pa |
Conversion chart
1 dB SPL2.24404e-5 Pa
5 dB SPL3.55656e-5 Pa
10 dB SPL0.0001 Pa
25 dB SPL0.0004 Pa
50 dB SPL0.0063 Pa
Worked example
1 dB SPL ≈ 0.000022440369086 Pa. Apply the selected conversion formula to other input values.
Unit definition
Decibels sound-pressure level (dB SPL) This unit is defined through the displayed non-linear relationship to pascal.
Unit history
Decibels sound-pressure level is represented here using its modern SI definition or an internationally accepted relationship to an SI base unit.
Step by step
1. Parse the value, including fractions.
2. Convert dB SPL to pascal.
3. Convert the base value to Pa and apply your display precision.
Understand the result before using it
Decibels sound-pressure level to Pascals converts a value measured in Decibels sound-pressure level (dB SPL) into the equivalent value in Pascals (Pa). The numerical value changes because the size and definition of the selected unit changes; the underlying quantity does not.
Calculated result
The conversion follows the displayed unit relationship. Display rounding can hide additional digits, and measured inputs cannot become more accurate merely by changing units.
Formula, assumptions, and example
Formula
result = 0.00002 × 10^(input ÷ 20) ÷ 1
Assumptions
- Decibels sound-pressure level and Pascals represent the same sound pressure quantity.
- The input is expressed in dB SPL; the output is expressed in Pa.
- The unit definitions and conventional relationship shown on this page apply.
Worked example
1 dB SPL ≈ 0.000022440369086 Pa. For another value, apply the same relationship and round only to the precision your source measurement supports.
When to use it
Good uses
- Read a dB SPL measurement in a document that expects Pa.
- Compare a decibels sound-pressure level value with a value reported in pascals.
- Check the dB SPL to Pa arithmetic before copying the result into another calculation.
Limitations
Common mistakes to avoid
- Decibel sound-pressure level is logarithmic and depends on the stated reference pressure.
- Round the output to a precision justified by the original measurement.
- Verify safety-critical, regulated, laboratory, and contractual conversions against the controlling standard.
Sources and further reading
These references explain the underlying standards or provide authoritative context. Your own contract, institution, clinician, product documentation, local code, or governing standard may be the controlling source.
Guidance on unit names, symbols, conversions, and numerical presentation.
Questions about this calculation
How do I convert Decibels sound-pressure level to Pascals?
result = 0.00002 × 10^(input ÷ 20) ÷ 1. Input is in dB SPL; result is in Pa. 1 dB SPL ≈ 0.000022440369086 Pa. The displayed digits may be rounded.
What is 1 dB SPL in Pa?
1 dB SPL ≈ 0.000022440369086 Pa. The displayed digits may be rounded. Use the full formula for other inputs; offset, reciprocal, and logarithmic scales cannot generally use this example as a multiplier.
Can I reverse the dB SPL to Pa conversion?
Yes. Swap the source and target units in the converter. The reverse relationship converts Pa back to dB SPL.
Is the Decibels sound-pressure level to Pascals result exact?
The conversion follows the displayed unit relationship. Display rounding can hide additional digits, and measured inputs cannot become more accurate merely by changing units.