Free audio to video converter

MP3 to Video

Turn an MP3 and your cover art into an MP4 for YouTube, TikTok, Reels or Shorts. Made in your browser: no sign-up, no upload, no watermark. Up to 10 minutes.

Looked after by Boom, a loudspeaker.

Shape
TikTok, Reels, Shorts, Stories
Background
Moving bar
Shows people the audio is playing, and how far along it is.

Made on your device: your audio and picture are never uploaded. Up to 10 minutes. Usually done in well under the length of the audio.

Your cover art shows here.

Audio-only show? Slice Audio makes clips from it

Want the best moments found and captioned automatically, with your hosts’ faces?

A full episode as one video is a fine thing to have on YouTube. Clips are what travel on TikTok, Reels and Shorts. Slice Audio, part of Shorts by Slice, reads the whole episode, picks the moments that make sense on their own, and draws each one as a captioned vertical clip in one of its templates, with your cover, your colours, and your hosts’ and guests’ photos and names. Your first 3 clips are free, with no card, and never watermarked.

Try Slice Audio See every template, playingVideo podcast? Shorts by Slice

How it works

  1. 1Add your audioMP3, M4A, WAV, OGG or FLAC.
  2. 2Add a pictureYour cover art, square works best.
  3. 3Pick the shapeVertical, square or 16:9 for YouTube.
  4. 4Make and downloadAn MP4, made on your device.

Questions

How do I turn an MP3 into an MP4 with a picture?
Add your MP3, add the picture (your podcast cover art works well), pick vertical, square or 16:9, and press Make my video. The MP4 is made right here in your browser and downloads when it is ready. There is nothing to install and no account.
Is my audio uploaded anywhere?
No. The audio and the picture never leave your device: the video is drawn and encoded by your browser. That is also why it is quick, and why it works on a slow connection.
How long can the audio be?
Up to 10 minutes per video. The whole video is held in your browser while it is made, and 10 minutes stays comfortably inside what a laptop or a phone can hold. For a longer episode, trim out the part you want to share first, or put the whole episode into Slice Audio, which finds the best moments and makes captioned clips of them.
Which size should I pick for YouTube, TikTok or Instagram?
Landscape 16:9 (1920x1080) for a normal YouTube video. Vertical 9:16 (1080x1920) for TikTok, Instagram Reels, YouTube Shorts and Stories. Square 1:1 (1080x1080) for the Instagram and LinkedIn feeds. Vertical keeps your cover and title clear of the bottom of the screen, where the apps put their captions.
Does it work in Safari and on an iPhone?
Yes. Chrome and Edge make the MP4 much faster than the audio plays. A browser without the fast video tools, such as an older Safari, makes it as the audio plays instead, so a 5-minute file takes about 5 minutes; the page tells you which it will do, and you keep the tab open. Firefox saves a WebM file, which YouTube accepts; for TikTok or Instagram, use Chrome or Safari for an MP4.
Is there a watermark?
No. The video is your picture, your title if you add one, and your audio. Nothing else is added.
Can it add captions, or find the best part for me?
This tool makes one video of the whole file, with no captions. Slice Audio, part of Shorts by Slice, does the rest: upload the whole episode and it picks the moments that stand on their own and makes each a captioned vertical clip, with your cover, colours, and your hosts’ and guests’ photos and names. Your first 3 clips are free.
MP3 to video: what to know

Why put audio in a video at all

YouTube, TikTok and Instagram only take video. A still picture with the sound is the simplest way to put an episode, a song or a voice note there. A moving waveform or progress bar tells people at a glance that something is playing and how far along it is.

The sizes it makes

Vertical 1080x1920, square 1080x1080, and landscape 1920x1080, at 24 frames a second with AAC sound, the format every one of those apps takes. For each platform’s full specs, see the social media video specs.

Pictures that work

Your podcast cover art is ideal: it is square and made to be read small. Check it against Apple’s rules with the podcast cover art checker. Any JPG, PNG or WebP works; a picture that is not square is cropped to the middle.

Whole episodes on YouTube

If you want every episode on YouTube as a still-image video, YouTube Studio can do that from your RSS feed. Our guide to putting an audio podcast on YouTube covers when that is worth it, and how to turn an audio podcast into video clips covers the other ways, from a still cover to Slice Audio.

Related free tools

MP3 to text for a transcript, the podcast loudness checker before you publish, and the YouTube chapters generator once the video is up.

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Shorts by Slice

From the team behind these free tools

One video. A week of posts.

Upload an episode and get back the moments worth posting, cut and captioned.

  • Reads the whole episode, then picks the excerpts worth posting
  • Captions burned in and framed vertical, ready to post
  • Your first 3 clips are free, no card
Try Shorts by Slice

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