Add Audio To An MP4 Video

Attach and edit an audio file to an MP4 file in just a few clicks. Edit videos and add your voiceover, music, or whatever audio in just a few minutes — all for free, with Descript.

How to add audio to an MP4 video file

Adding MP3 audio to your MP4 video clip is MPsimple. Follow this step-by-step process to add music, voiceover, or other sound effects to your clip.

Step 1

Drag and drop your MP4 video file into a project in Descript’s video editor. Wait a few seconds while Descript automatically transcribes any spoken audio in your video. Then make your edits by changing the transcript just like you would a Word doc — Descript will edit the corresponding audio and video for you.

Step 2

Select the audio (music track, voiceover, background music, etc.) that you want to add to your clip and drag it to the place in the transcript where you want it to play. Then adjust the time or volume it plays by clicking on the audio in the timeline. If it’s voiceover narration, Descript will transcribe that too, and you can edit the audio by editing the text in the transcript.

Step 3

Export your clip with its new audio as an MP4 video. You can export directly to YouTube in a few clicks, or save it on your computer to upload to Instagram, TikTok, or wherever you want to share it.

Frequently Asked Questions

What file formats does Descript’s video editing tools work with?

Descript is able to work with a wide range of encoding formats. For video, Descript works with MP4, avi, mov, mkv, wmv, wma, and others. Descript also works with a number of audio formats, including aac, mp3, wav, and more.

Do projects made in Descript have a watermark?

Video projects created and published using Descript’s Creator and Pro plans export completely watermark-free. Projects exported using Descript’s Free plan carry a watermark.

What resolution video does Descript support?

Descript can import and edit video formats all the way up to 4K. Descript users are able to import video files of all types and edit them directly in Descript, including adding new audio. If you’re exporting your video file, Descript’s Creator and Pro versions can export your video at any resolution, while Descript’s Free plan exports files up to 720p.

Can I publish my clip straight from Descript?

Descript provides a number of ways to publish your new video creation through a number of output formats. Your video can be uploaded directly to YouTube, or exported as an MP4 file, perfect for upload to Google Drive, Dropbox, or playing in players like iTunes or VLC media player. Descript can also turn your creation into a GIF.

Download the app for free

Create a podcast, a video, and all your social assets using Descript. It’s as easy as editing a doc.