Video & audio converter
MP3 to MP4 Converter
Turn an audio file into an MP4 video with a cover image or a plain background, ready to post.
Tested by Thiago · Updated
Free, no sign-up · Sent over HTTPS · Files are deleted from our server automatically after 30 minutes
How to convert MP3 to MP4
- Add your files: drag them into the box above, or click "Choose files".
- Click "Convert to MP4" and wait a few seconds while we process them.
- Download your MP4 files. Uploaded files are deleted right away, and converted files are removed from our server after 30 minutes.
Why convert MP3 to MP4?
YouTube, Instagram, TikTok and many other platforms only accept video, not plain audio. Converting MP3 to MP4 turns your song, podcast episode or voice recording into a video with a cover image or a clean background, so you can upload it anywhere videos are accepted.
- You want to publish a podcast episode or song on YouTube.
- You need to share audio on a platform that only accepts video.
- You want to add artwork or a cover image to a recording.
Picking a cover image that looks right
The video takes the shape of your image. Nothing is stretched and no bars are added, so the picture you choose decides whether the result is wide, square or tall.
- For a widescreen video, use a 16:9 image, for example 1920 by 1080 pixels. That is the largest size the video can have.
- A normal 4:3 phone photo becomes a 1440 by 1080 video. We tested with a 4000 by 3000 photo and that is exactly what came out.
- A tall phone photo makes a vertical video, but only up to 1080 pixels high: a 3:4 portrait photo ends up at 810 by 1080.
- Small images are not enlarged, so a 600-pixel logo makes a 600-pixel video. Start from a big, sharp picture.
- Photos taken with the phone turned sideways are straightened first, so they appear the right way up.
What is inside the MP4 and why it is bigger than the MP3
The sound is re-encoded as AAC at 192 kbps, which takes about 1.44 MB per minute. Starting from an MP3 this is a second round of compression. It is hard to hear at this bitrate, but if you have the same recording as WAV or FLAC, upload that instead.
The picture costs very little, because the still image is stored as one frame per second. In our test the photo cover added roughly 0.5 MB per minute, and the plain dark background added almost nothing. So expect the MP4 to be somewhat larger than a typical MP3 of the same audio, not many times larger.
Tips for the best result
- Add a cover image (JPG, PNG or WEBP) for a much nicer result; without one, we use a clean dark background.
- The video lasts as long as your audio.
- Besides MP3, you can also upload WAV, M4A, AAC, OGG or FLAC files.
About these formats
MP3: The most popular audio format. It compresses sound to a small size while keeping good quality, and it plays on any device.
MP4: The most widely supported video format. It plays on phones, browsers, TVs and social networks, with good quality at a reasonable size.
Frequently asked questions
Can I add an image to my MP3?
Yes. Choose a cover image and it will be shown for the whole length of the audio.
What size is the cover image in the video?
Your image is kept at its original proportions, up to 1920 by 1080 pixels.
Will YouTube accept the MP4?
Yes. The video uses H.264 and AAC, the formats YouTube and social networks recommend.
Why is my MP4 larger than the MP3?
The audio is stored at 192 kbps, which is often more than the MP3 had, and the cover image adds a little on top. A long recording with a detailed photo grows the most.
Can I make a vertical video for phones?
Yes. Use a tall image and the video will be vertical. The height is limited to 1080 pixels, so a 3:4 photo gives 810 by 1080.
Can I use a PNG with a transparent background as the cover?
You can upload it, but a video cannot be transparent. Place the logo on a solid background in an image editor first so you control the color.