• November 7, 2018 4:00PM EST
• November 7, 2018

You enjoy watching and listening to music videos on YouTube. If only there was a way to listen to the audio portion offline. If you have the right tools, there is. Certain websites, software, and browser extensions can strip out the audio portion of any YouTube video and convert it to an MP3 file, which you can then save to your computer or mobile device.

We've previously covered how to download YouTube content as video files. Here, I'll focus on the task of downloading them as audio files.

Before diving in, though, let's get one thorny issue out of the way. Is this type of conversion and download legal? That depends on the video. You can certainly convert and download your own personal YouTube videos, as well as public domain and non-copyrighted videos; just search YouTube for 'public domain' and 'non-copyrighted' content. But you can't legally convert and download copyrighted videos without the owner's permission.

As a word of warning, a spokesperson for Google sent me the following statement: 'Our Terms of Service prohibit the downloading or copying of videos on YouTube without explicit consent from the copyright holder. Once notified of an infringing tool or service that allows the downloading of a YouTube video without permission from the content owner we take appropriate action.'

With those caveats in mind, let's check out some ways to convert the right videos to audios.

• YouTube Music

  Here's one option off the bat if you just want to listen to YouTube music and don't need an MP3 file. YouTube offers its own app for listening to your favorite music. With YouTube Music for iOS or Android, you can browse and search for music from different artists, albums, and genres on YouTube. You can't download songs with the free version, but you can with the premium edition, though you can listen to them only within the app.

  You can select specific artists that you like, and the app spins up a playlist of recommended channels. The latest popular videos are served up through a video hotlist. The app keeps track of the music and channels you access so you can easily return to them. And you can create your own library of your favorite music.

  The basic version of YouTube Music is free. YouTube Music Premium is a paid option that strips out the ads, can play music in the background while you use your device, and lets you download music and playlists to listen to offline within the app. You can try out YouTube Music Premium with a free one-month trial. To continue, you'll have to shell out $9.99 a month for Android or $12.99 a month for iOS. Yes, Apple charges 30 percent extra for the subscription, but you can avoid the added cost by signing up on the web for $9.99 and accessing your premium account on your iPhone or iPad.

• YouTubeMP3.is

  Quick and convenient, YouTubeMP3.is is a website where you can copy and paste the URL of the YouTube video you want to convert. Just add the link, click on the Download button, and the file conversion kicks off. While the video is being converted and downloaded, you can convert another file if you wish. From there, listen to the file on your PC via your favorite music player and/or copy it to your mobile device. The file downloads can take awhile as the conversion is done in real time second by second, but the results are worth the wait.

• GenYouTube

  Another user-friendly website, GenYouTube converts YouTube videos to MP3s as well as other formats for audio and video. Copy and paste the link to a YouTube video in the search field. GenYouTube starts playing the video. You then select the format for the audio file, such as MP3 or M4A. Download the file and you can play it on your PC and then copy or sync it to your mobile device.

  GenYouTube has a couple of other tricks up its sleeve. If you're watching a video on YouTube, simply add the word gen to the video link, as in https://www.genyoutube.com/watch?v=qZXdZwsx64I, and you're swept away to the GenYouTube site to download the video. You can also tap into the service by installing browser extensions in Firefox, Chrome, and Safari.

• 4K Video Downloader

  Here's a conversion program that you download and run on your Windows PC or Mac. The basic version of 4K Video Downloader is free. If you want to cut out the ads, download YouTube playlists and channels, and receive future updates to the software, the premium version costs $15 for three personal licenses.

  With 4K Video Downloader, you can convert and download YouTube videos as video or audio files. For audio files, you can choose among MP3, M4A, and OGG formats, and opt for the original quality, high quality, medium quality, or low quality. To use the software, open YouTube and copy the URL of the video you want to convert. Segue to 4K Video Downloader and click on the Paste Link button. You then pick the format and quality of the audio as well as the download location. Click on the Extract button. Double-click on the file in the software or in File Explorer on Windows and Finder on the Mac to play the audio.

• MP3 Rocket

  Another program that you can install and run on Windows or macOS, MP3 Rocket is quite versatile. You can convert and download videos from YouTube and other websites into video or audio files. You can search for videos by name or topic across a range of websites rather than having to hunt each site separately. To stay on the safe side of the law, you can even specify videos with Creative Commons licenses that you can legally and freely use. MP3 Rocket also includes a built-in file manager for viewing and playing your downloaded and converted clips.

  To convert a video from YouTube or another site, simply copy and paste the URL into MP3 Rocket and click on the Convert button. From there, choose the format, bitrate, filename, and location for the file. Click OK, and the conversion and download process runs. You can then listen to and control the audio within MP3 Rocket through its integrated player or open the file from File Manager or Finder. The software displays a list of all the files you've converted so you can easily access and play any of them.

  The basic version of MP3 Rocket is free. For $24.97 a year, $34.97 for two years, or $44.43 for lifetime access, MP3 Rocket Pro offers more formats, faster downloads, and other bonus features.