We tested two important attributes of audio converter software that you won’t find information about on spec sheets or marketing materials: speed of conversion and ease of use. After testing these products, we can recommend specific programs that are the fastest, easiest to use, best for recording streamed content and the best free converter software.

Our testing and research focused on each program’s audio conversion capabilities, but keep in mind that you can use these products to convert video files too.

Fastest Audio Converter

Fastest Audio Converter: Switch

During our tests, Switch converted a 625MB WAV file to MP3 in 40 seconds. That is 23 seconds faster than the second-fastest product we reviewed. The program is available for both Mac and PC, and it is one of the easiest to navigate. It can import 45 different file types and convert them to 26 output formats. Not only is it fast, but it is one of the best overall music converters available.

Easiest to Use

Easiest to Use: Xilisoft Audio Converter

Xilisoft Audio Converter is the easiest program to use of the audio converter software we tested. It only takes a couple clicks to convert audio files, and the user interface has an intuitive layout. If you are nervous about learning how to use a new kind of software, you can rest assured that this audio converter makes the process as simple and straightforward as possible.

Best Streaming Recorder

Best Streaming Recorder: Audials

Audials Tunebite Platinum can record any audio material that passes through your computer’s sound card. That means you can record a playlist from your favorite streaming service, like Pandora or Spotify, and convert it to an MP3 so you can put it on a music player or mobile device. This converter software can also record and convert streamed video from services like Netflix and Amazon Prime Video.

Best Free Converter

Best Free Converter: Freemake

Freemake isn’t as fast as the best for-pay converter software we tested, but it is easy to use, and you can download the full version of the program for free. This audio converter application ran smoothly in our tests, without any sign of the unwanted additional software, malware or adware normally associated with free software downloads.

How It Works

One of the most popular reasons people use audio converters is file compression. When you compress a file, it starts in a format that takes up a lot of space on your hard drive, such as WAV, and condenses to a format that takes up less space such as MP3. File compression takes away bits of data from the original file, and the result is a "lossy" file.

Removing data from a file is referred to as lowering the bitrate. The bitrate is the amount of data that is processed over time, and it’s measured in kilobits per second (kbps). When you take a song that is at 320 kbps and lower it to 128 kbps to save space, you remove data that can't be replaced. Lowering the bitrate makes the file smaller so you can store more on your computer, but it also lowers the audio quality.

Once you compress a file and take data away, you can't reverse it. You can turn an MP3 back into a lossless file format like WAV, but changing the file type doesn’t revert the audio quality back to its original state. This is an issue if you want to upgrade your entire library of MP3s to a higher-quality format – you need to go back to the original audio source to convert to a lossless format.

The audio converter programs we tested for this buying guide range in price from free to $40. Conversion programs you purchase come with advanced features – for example, they can extract audio from video and record streamed content – and they are faster than free software.

Conversion Speed

Speed may be nothing more than a convenience for some, but when you have many large files to convert, a fast program can save you valuable time in the long run. We took a 625MB WAV file and compressed it to a 26MB MP3 with each software. During this test, we timed each application to see which one has the fastest compression speed. We tested the programs one at a time using the same computer and the same settings for files and conversions. Keep in mind that compression speeds may vary depending on your personal computer's performance.

Ease of Use

Performance is paramount for audio conversion software, but the program should also be easy to use. While the products we reviewed have the same basic functionality, they differ in how accessible their tools are. We created tests to break down the process of converting files in each software. Whether we were converting files, extracting audio from video or ripping an audio CD, we found the most user-friendly audio converters only require a couple mouse clicks to complete a task.