Add Audio to Video
Add background music, voiceovers, or sound effects to any video. Replace the original audio track or mix both. MP4 output. 500 MB. Free, no watermark.
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Subtitle: SRT, VTT, ASS, TXT, CSV · Video: MP4, MKV, WebM, MOV · Audio: MP3, WAV, AAC, FLAC · Free, no sign-up
How to use this tool
Three easy steps. No sign-up needed for your first file.
Upload video + audio
Drop your video file (MP4, MKV, MOV) and audio file (MP3, WAV). Up to 500 MB each.
Choose audio mix mode
Replace original audio entirely, mix both at adjustable volumes, or add as new track.
Download enhanced video
Get your video with the new audio. MP4 with H.264 + AAC. No quality loss on video stream.
Frequently asked questions
Can I add background music without removing the original audio?
What audio formats are supported?
Will adding audio reduce video quality?
Can I add multiple audio tracks?
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Try free →Ready to use Add Audio to Video?
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