MP3 to MP4: Turn Audio into a Video with a Picture
Drop an MP3 and a picture, pick 16:9, square or 9:16, and download an MP4 video for YouTube. Cover art inside the MP3 is used if you add no picture.
Drop an MP3, or WAV, M4A, FLAC, OGG and more
Supported: MP3, WAV, M4A, AAC, FLAC, OGG, OGA, OPUS, AMR, 3GA, AWB, WMA, AIF, AIFF, CAF, WEBA, MKA
Drop an MP3, or WAV, M4A, FLAC, OGG and more
Glad it worked. SubtitleKit is free and runs on tips. Still free, still runs on tips.
How to turn an MP3 into an MP4
Drop your MP3
Drag it onto the page, or click to choose it. Its length shows up straight away, and any cover art inside it becomes the picture.
Add a picture
Drop a JPG, PNG or WebP, or keep the cover art. With no picture at all, the video is black.
Pick the shape
Choose 16:9 for YouTube, 1:1 for a square post or 9:16 for Shorts. Fit shows the whole picture; Fill crops it to the frame.
Convert and download
Press Convert to MP4, play the result if you like, then press Download MP4. The file keeps your MP3's name.
Give an MP3 a picture so it can go on YouTube
YouTube and many other sites take video files, not audio files. This tool pairs your MP3 with one picture and writes an MP4 that shows the picture for as long as the sound plays, ready to upload.
How MP3 to MP4 conversion works
Your browser reads the MP3 first, so its length, its format and any cover art inside it show up at once. When you press Convert to MP4, it encodes the sound as AAC, draws your picture in the shape you chose and writes both into one MP4 file. Rarer formats such as AMR, WMA and AIFF go through a converter that downloads once and is then cached. Already have a video? Use MP4 to MP3 to take the sound out of a video.
MP3, WAV, M4A, FLAC or OGG in, MP4 out
The page takes MP3, WAV, M4A, AAC, FLAC, OGG and Opus, plus AMR, WMA and AIFF. The picture can be a JPG, PNG, WebP or AVIF; a GIF gives its first frame. The video is H.264 with AAC sound, encoded at 192 kb/s unless the file already holds AAC, in 1920×1080 for 16:9, 1080×1080 for square or 1080×1920 for 9:16.
Your audio stays on your device
The MP3 and the picture stay on your device. Your browser reads and converts them and sends them nowhere, which is also why a long recording starts right away instead of waiting for an upload. An internet connection is needed to load the page, and once for the converter that handles rarer formats.
Limits
Speed depends on your device and browser. MP3, WAV and FLAC sound has to be encoded, which is slow in Firefox on a computer and on phones; an M4A with AAC sound is copied, so it is fast everywhere. The finished video is built in your browser's memory, so a recording longer than about 5 hours may have to be split first, and one longer than about 15 hours always does. HEIC photos do not open here; save them as JPG first. The video is one still picture, with no waveform or animation.
Frequently Asked Questions
How do I upload an MP3 to YouTube?
YouTube takes video files, not MP3s. Make the MP4 here with a picture, then upload it in YouTube Studio like any other video.
Can I use the album cover?
Yes. If the MP3 has cover art and you add no picture, the video shows the cover. Adding your own picture replaces it.
Which shape should I pick for YouTube Shorts?
Pick 9:16, which makes a vertical 1080×1920 video.
Does it re-encode my audio?
MP3, WAV and FLAC sound is encoded to AAC at 192 kb/s, the sound MP4 players expect. An M4A with AAC sound is copied as it is. The screen says which one applies to your file before you convert it.
Why is the video one frame per second?
A still picture needs no more. The file stays small and is made fast.
Is there a watermark?
No. The video shows your picture and nothing else.
Can I use a WAV file?
Yes, on this page. Drop the WAV the same way; the sound is encoded to AAC, so the video comes out much smaller than the WAV.
Why is it slow in Firefox?
Firefox on a computer has no built-in AAC encoder, so MP3, WAV and FLAC convert slowly there. On Windows and Mac, Chrome or Edge take seconds. M4A files with AAC sound are copied and fast in every browser.
Does it work on my phone?
Chrome on Android and Safari on iPhone, yes; Firefox for Android can't make video files. On a phone, converting the sound of a long MP3 can take several minutes; an M4A with AAC sound is fast.
Tips for a good picture video
Use a picture as big as the video. For 16:9 that is 1920 pixels wide. A smaller picture is scaled up and looks soft on a large screen.
Pick Fit to keep the whole picture, with a dimmed copy of it filling the edges. Pick Fill when the picture can lose its edges.
If a picture will not open, save it as JPG or PNG and add it again.
