Convert MP3 to MP4, Free
Upload your MP3 file and get a MP4 in seconds. No account, no watermark.
How to convert MP3 to MP4
MP3 is a pure audio format that cannot be uploaded to video platforms like YouTube, which require a video container. Converting an MP3 to MP4 wraps the audio in a video container with a static black frame or image, making it suitable for YouTube uploads, video editors that require MP4 input, or any workflow that expects a video file.
BoltConverter wraps your MP3 audio in an MP4 container on its servers. The audio quality is completely preserved since no re-encoding of the audio track is needed. The result is an MP4 file you can upload to YouTube or use anywhere a video file is expected.
Upload your MP3 file
Click the upload area or drag your .mp3 file onto the page. Files up to 100 MB are accepted.
Conversion runs on the server
Your MP3 audio track is packaged into an MP4 container with a minimal video stream.
Wait a moment
Most MP3 files convert in seconds.
Download the MP4
Click Download to save the MP4. Your MP3 is deleted from the server after conversion.
Frequently asked questions
Will the audio quality change?
No. The MP3 audio track is remuxed into the MP4 container without re-encoding. The audio bitrate and quality are identical to the original MP3.
What will the video look like on YouTube?
The video will show a black frame for the entire duration of the audio. If you want a thumbnail image instead, you can add a cover image in YouTube Studio after uploading.
Can I use this to upload music to YouTube?
Yes. Many artists upload music videos with a static image background on YouTube. Convert your MP3 to MP4 here, then upload and add a thumbnail in YouTube Studio.
Is there a file size limit?
BoltConverter accepts files up to 100 MB. Most MP3 tracks are well under this limit.
Are my files kept private?
Your file is uploaded over HTTPS and deleted from the server immediately after conversion.