How to Reduce Background Noise in Audacity

  • Difficulty Medium
  • Time required 5 Minutes

Do you want to remove background noise from an audio track? You can do this easily with a free software called Audacity, which can be downloaded here:

Step 1

Download and open Audacity on your computer. Then upload your audio file. Audacity supports a range of file formats such as MP3, WAV, and more. For a list of supported file formats, click here.

Step 2

Select a section of audio with no visible sound waves. Click and drag your mouse over the desired area to select it. 

Step 3

Next click on Effect at the top and select Noise Reduction.

Step 4

This will cause a new menu to pop up, all you need to do is click OK at the bottom. The default Noise Reduction settings are going to work for most audio files.

Here is extra information in case you do want to adjust the default settings and change Reduction, Sensitivity, or Frequency Smoothing. This information is copied from the Audacity Team Manual.​​​​​​

  • Noise Reduction (dB): Controls the amount of volume reduction to be applied to the identified noise. Use the lowest value that reduces the noise to an acceptable level. Higher values than necessary may make the noise even quieter, but will result in damage to the audio that remains.
  • Sensitivity: Controls how much of the audio will be considered as noise, on a scale of 0 (off) to 24 (maximum). Greater sensitivity means that more noise will be removed, possibly at the expense of removing some of the desired signal as well. Lower values may result in the appearance of artifacts in the noise-reduced audio. Set this control to the lowest value that achieves effective noise removal without the introduction of artifacts.
  • Frequency Smoothing (bands): At values of 1 or higher, this control spreads the noise reduction into the specified number of neighboring bands. This modifies the signal you were intending to keep, but if artifacts remain in the noise-reduced audio the smoothing can make those artifacts sound more acceptable. There is a chance that smoothing will make the desired audio less clear, so where your desired signal is strong and of wide frequency range and the noise is light, try leaving this control at 0 (off).

Step 5

Now select all audio by holding down the Ctrl  and keys on your keyboard. All of the audio should now be selected. 

Step 6

Finally, click on Effect at the top and select Repeat Noise Reduction.

Step 7

You now have an audio track with reduced background noise! All you need to do now is click on File and Export to export your audio as an MP3 or WAV file.


Further reading:



Audacity Audio Recording Noise Reduction Audio Production Sound