If you’re on Windows 8, try downloading the free Decibel Reader app from the Microsoft App store. The app uses your computer’s microphone to read noises up to 96 decibels. Similar devices are available from the iTunes app store for Apple products. [2] X Research source You can also try using a third-party program to measure decibels. For instance, Audacity, a free sound recording program, includes a simple built-in decibel meter.

For Apple devices: Decibel 10th, Decibel Meter Pro, dB Meter, Sound Level Meter For Android devices: Sound Meter, Decibel Meter, Noise Meter, decibel For Windows phones: Decibel Meter Free, Cyberx Decibel Meter, Decibel Meter Pro

Note that decibel meters/sound level meters can go by other names. For instance, another type of tool called a “noise dosimeter” performs basically the same function as a standard sound level meter.

Note that, for ordinary sounds, the intensity value is usually very small. For instance, a sound with an intensity of 5 ×10-5 (or 0. 00005) watts/square meter translates to about 80 decibels — about the volume of a blender or food processor. To better understand the relationship between intensity measurements and decibels, let’s follow along with an example problem. For the purposes of this problem, let’s say that we’re music producers and we’re trying to find the background noise level in our recording studio to improve the sound of our records. After setting up our equipment, we detect a background noise intensity of 1 × 10-11 (0. 00000000001) watts/square meter . In the next few steps, we’ll use this info to find the decibel level of the background noise in our studio.

In our example, we’d divide our intensity value, 10-11, by 10-12 to get 10-11/10-12 = 10.

Our example is easy to solve. Log10(10) = 1. 1 ×10 = 10. Therefore, the background noise in our studio has a loudness of 10 decibels. This is quite quiet, but still detectable with our high-quality recording equipment, so we’ll probably need to eliminate the source of the noise for the best recordings

Consider this — which is easier to use: 55 decibels or 3 × 10-7 watts/square meter? The two are equivalent, so rather than having to use scientific notation (or a very small decimal), decibels allow for us to use a sort of simple shorthand for easy everyday use.