MP3 Compressor: How to Compress MP3 on Mac (Mojave Included) and Windows

by Brian Fisher • • Proven solutions

For music enthusiasts storage space is always a struggling issue, as there is never ending files to be kept. File compression is one of the most straightforward solutions to the problem as it allows you to create more space on your device by reducing the file size. So do not delete your favorite MP3 files when you can reduce MP3 file size. A roundup of the best MP3 compressor tools is given below.

Part 1. Best MP3 Compressor to Shrink MP3 Files

To compress MP3 audio files in best quality output, we recommend UniConverter. This professional program allows compressing your MP3 as well as other popular audio formats in excellent quality output files. The compression of the file takes place by altering the parameters like channel, bit rate, sample rate, quality, and others. The program also facilitates the conversion of MP3 files to other audio formats as needed. The entire process of compression completes in just a few simple steps and is fast.

Get the Best MP3 Compressor:

  • Allows compressing MP3 and other audio files in high quality, including WAV, AAC, OGG and more
  • Shrink MP3 file size by changing its bit rate, sample rate, quality, encoder, channel, and other parameters
  • Facilitates batch processing by adding multiple files at a time
  • Super fast compression speed
  • Compressed files can be transferred to an array of devices like iPhone, Android, and others
  • Facilitates downloading YouTube videos to MP3 format
  • Powerful Toolbox: GIF maker, video downloader, video recorder, DVD/CD burner, VR converter, etc.
  • Support to Windows and Mac system

Guide to compress MP3 files using UniConverter

Before getting started, you can watch the video below to get a quick look over how to compress MP3 audio files.

Step 1: Run iSkysoft MP3 compressor and add MP3 files

Open UniConverteron your PC and to add local MP3 files click on +Add Files from the Convert tab. You can even drag and drop the files.

Run iSkysoft MP3 compressor and add MP3 files

Step 2. Choose target format and adjust settings for smaller size

Open the drop-down menu beside Convert all files to: option and from the Audio tab, choose MP3 or other target formats as desired. Select Low-Quality option to reduce the file size.

Choose target format and adjust settings for smaller size

To further adjust the file parameter settings, click the edit icon or hit on the +Create Custom button that will open a new Settings window. From here change the channel, bit rate, encoder, and sample rate of the file. Click on Create button to confirm the changes.

Step 3. Compress MP3 file

You can see the change in the file size from the Source menu and the Target menu. Finally, click on Convert All button to start converting and compressing your added MP3 files. The processed files get saved at the location mentioned on Output tab. The files can also be managed from the Converted tab on the software interface.

Compress MP3 file

Part 2. How to Compress MP3 with Audacity

Audacity is free and open source application software that facilitates editing of digital audio files including file compression. The program is compatible with Windows, Mac, and Unix like systems. The application once installed allows you to record, export, and import the audio files in an array of formats. Audio file editing can be done using features like cut, copy, paste, and others. Video compression using Audacity can be done by using the encoding and sampling options along with the change in file parameters.

Step 1. Download, install and open Audacity app on your PC. Open the desired MP3 file in the app that you wish to compress.

Step 2. Move to File > Export option

Step 3.Hit on the Options menu and then choose the Bit Rate Mode. Next, choose from the preset available for variable and average constant.

Step 4.Finally, hit on the Save button and then OK to complete the compression process.

How to Compress MP3 with  Audacity

Audacity and UniConverter both support MP3 file compression but with a different set of features. The table below compares both the program on various parameters that can be used to make a choice depending on your requirements.

Platform Windows and Mac Windows, Mac, and Linux
Supported input formats Almost all audio and video formats Limited Popularly used formats
Batch processing Yes Not supported
Change in file parameters for compression Yes, including audio encoder, channel, sample rate, bitrate and more Limited options for parameter editing
File conversion Yes, support to conversion in 150+ formats No
File transfer Yes No
Download online video Yes No
Edit video Yes No

Part 3. Compress MP3 Online Free

#1. MP3Smaller

Using this online MP3 converterprogram you can reduce mp3 file size online free in decent quality. The local files from your PC can be added to the program for the process. 150MB is the maximum file size that can be added to the program for compression. You can choose the size of the file in terms of bitrate so as to reduce the file size accordingly. The processed files can be downloaded from the program interface. To maintain the security, uploaded files are deleted after a time.


Disadvantages of using online tools

Simplicity and no software installation are the benefits associated with online programs. On the flip side, there are a number of disadvantages as well.

  • Supports limited file formats for compression as compared to professional tools
  • Dependent on internet connectivity
  • Limited options to edit file parameters for compression
  • Restriction to the file size and number of files that can be added for the process
  • Limited additional features

#2. YouCompress

This online app for MP3 compression is simple and fast to use and process your files straight from your browser window. Using the program you just need to add the MP3 files from your PC and they are then compressed using the best settings. Once the MP3 files are reduced in size, you can download the same on your PC from the interface. There is no restriction to the number of files that can be compressed using the software. The sound compressor is safe to use and has no watermark on the files.


#3. Online Converter

Using this online converter you can make MP3 smaller on your PC as well as from online sources using their URL. Maximum supported file size for the process if 200MB. Once the file is added to the interface, you need to choose the quality of the output file from the given options so as to compress the file. Once the file is uploaded and processed, you can download the same form the app interface. There are also options to share the processed files to an array of social networking platforms like Facebook, Twitter, Google+ and others. You can even send the compressed file to your phone and download it there using this music compressor.

 Online Converter

Part 4. How does MP3 Compression Work?

For any type of file compression, the compression algorithm is used. When it comes to music or sound, perceptual noise shaping is the technique. The technique is called perceptual as MP3 file features the characteristics of the ear in order to formulate the algorithm.

There are a number of sounds that human ear cannot hear, hear it in a better manner and hear the louder one as compared to the software one. Considering all these factors, it can be said that there are a number of MP3 file parts that can be removed without affecting the quality of the file and these are used for MP3 compression. The lossy format of the MP3 file is created after the compression process for the size reduction.

Related Articles & Tips

This article will show you how to compress WAV files on Mac and Windows with online video compressor, we also recommend you choose the best video toolbox - UniConverter.
Find the steps on how to compress videos in iMovie. You can easily resize video with iMovie or with the best video compressor iSkysoft Video Converter Ultimate.
How to compress a video on iphone so that you can save more space to reserve more wonderful videos? Here you can find best video compressors for iPhone.
Need some software to compress video to help you store more videos? Here you can find best Video compressors on Mac.

Brian Fisher

staff Editor

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