Merge audio with video voiceover, dubbing & BGM
Replace the original soundtrack or mix a new track on top—ideal for MP4 dubs, narration, and light background music. Export MP4, MKV, or WebM, track every job, and download when ready.
How merging works
Upload video
Bring MP4, MOV, WEBM, AVI, MKV, or other supported cuts from your device.
Upload audio
Add MP3, WAV, AAC, M4A, FLAC, or OGG—the track you want merged in.
Choose mode & format
Pick replace or mix, then MP4, MKV, or WebM before you queue the job.
Download merged file
Follow progress in the task list and save the finished render to your machine.
Why teams use this merge flow
Replace or mix in one panel
No separate DAW session required for simple swaps—switch modes without leaving the browser workflow.
Task history stays visible
Processing, failures, and completed renders stay in one list so nothing disappears behind a spinner.
Built for quick handoffs
Perfect for social cuts, course modules, and client reviews that need a new VO layer fast.
Why merge inside SnapVee Studio?
Compared with dumping files into random mux tools, this flow keeps auth, progress, and delivery aligned.
Signed-in jobs with replace/mix modes and MP4/MKV/WebM outputs in one place.
Progress bars and statuses stay attached to each merge task.
Outputs stick around for about 24h so you can download after review.
Often a single anonymous upload with almost no feedback while you wait.
Hard to tell whether audio replaced or mixed until you download blindly.
Little guidance on retention, limits, or what to do when a job fails.
What users say
Operators who ship narrated clips, training media, and social edits every week.
“We drop course VO in replace mode and the MP4 is client-ready minutes later—no more bouncing through three desktop apps.”
“Mix mode lets me keep light room tone under a new read. The task list means I can batch several merges without losing track.”
“MKV exports for our finishing team and MP4 for approvals—all from the same merge panel. Huge for turnaround days.”
Merge video and audio — FAQ
Long-tail answers for replacing a track, mixing voiceover, and export formats.
How do I add voiceover or dubbing audio to an MP4 online?
Upload your video and a separate audio file, choose Replace to swap the original track or Mix to blend with it, then pick MP4, MKV, or WebM. Sign in to run the job and download from the task list when it finishes.
What is the difference between replace and mix audio mode?
Replace removes the video’s original audio and uses your new file as the only soundtrack. Mix keeps the original audio and layers your file on top—useful for light background music when levels are balanced.
Can I merge audio with video and export MKV or WebM?
Yes. After both files are selected you can choose MP4, MKV, or WebM as the container before starting the merge task.
Do I need an account to merge video and audio?
Yes. Merge runs after you sign in so tasks can be tracked and results delivered securely.
How long are merged files available to download?
Outputs are kept for about 24 hours before automatic cleanup. Download copies to your device as soon as the task completes.
Ready to lay in new audio?
Sign in, upload your video and audio, pick replace or mix, then grab the merged file when the job completes.