Created By : Vaibhavi Kumari

Reviewed By : Rajashekhar Valipishetty

Last Updated : May 17, 2023

The dB Calculator here saves you time by providing you with the sound pressure and sound intensity levels in decibels. To obtain the outputs, simply enter the inputs in the designated input fields and click the compute button. It can be used for dB conversion and determining the distance between a sound source and the listener.

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Reference pressure(Pref):

Sound Pressure Level (SPL)

When we hear a loud noise, we get negative feelings as a result of the pressure of the sound waves. This pressure can be measured in pascals, however, measuring in decibels is more practical. The Sound Pressure Level (SPL) is a measurement of sound pressure about the human hearing threshold. SPL = 20log(P/Pref) is the formula for calculating SPL.

The sound pressure level, measured in decibels, is referred to as SPL. The sound wave pressure is measured in Pascals. Pref is the sound pressure reference value, which is considered to be 0.00002 Pa.

Level of Sound Intensity

The sound wave power per unit area is measured by the Sound Intensity Level. It's a unit of measurement for the amount of energy released each second per square metre.

SIL = 10log(I/Iref)

  • Where, SIL = Sound Intensity Level in decibels
  • I = Sound Intensity in Watts Per Square Meter The reference value, Iref, is commonly 1×10⁻¹² W/m².

For more concepts check out to get quick answers by using the free tools available.

Sound Intensity at a Distance

Sound intensity varies with distance from the source in general. The phenomenon is known as distance attenuation, and it is a simple basic sense.

It is simply because the energy of sound is diffused over a broader region from a physical standpoint. Consider a sphere that is encircled by a constant sound source. Even though the amount of energy emitted by the source remains constant, the sphere grows in size and its surface expands. The energy is dispersed across the sphere's surface. The equation can be written as I = P/(4πR²), Where, R = sphere's radius D = distance from the sound source.

Converting from Pascals to Decibels

Our decibel calculator can be used to calculate the decibel equivalent of sound wave pressure. To find the sound pressure level, simply enter the pressure in pascals into the dB calculator. If SPL is given, you can use this tool in reverse to find the pressure.

FAQs on dB Calculator

1. What are the Sound Intensity Level units?

Watts Per Meter Squared (W/m^2) is the unit of sound intensity level.

2. Is 20 dB twice as loud as 10db?

A sound with a decibel level of 20 is ten times louder than one with a decibel level of 10. The noise level in a quiet bedroom is 30 decibels, which is 100 decibels louder than 10 decibels. And 40 decibels is 1,000 decibels louder than ten decibels.

3. Is dB a Unit of Measurement?

Yes, dB is a sound measurement unit.

4. How much do decibels decrease with distance?

The sound intensity drops by 6 decibels (dB) with every doubling of distance.

5. What is the formula for calculating sound pressure level?

SPL = 20log(P/Pref) is a formula for calculating sound pressure level.

6. Is the decibel scale linear?

When you use a sound level metre to measure noise levels, you use decibel units (dB) to quantify the strength of the noise. So, rather than utilising a linear scale, a logarithmic scale with 10 as the base is utilised to depict sound levels in more comprehensible quantities. The decibel scale is the name for this scale.