Replace or add an audio track to a video, trimmed to the shorter of the two, all on your device.
Plenty of videos need the right sound laid over them. A silent screen recording wants a voiceover, a montage needs a music bed, a product clip should carry a narration track, or footage with useless on-location noise should be swapped for something cleaner. Doing that by hand usually means opening an editor and wrestling with two timelines. This tool takes one video and one audio file and combines them into a single MP4 for you.
Drop in your video, add the audio track you want on it, and run it. The tool marries the two into one file and downloads the result. It fits the finished clip to the shorter of the two inputs, so if your music is longer than the video, the extra music is trimmed, and if the video runs longer than the audio, the video is cut to where the sound ends. That keeps the pairing tidy without a silent tail.
For quality, the tool keeps your original video stream as it is and only encodes the new audio, so the picture is not re-compressed and loses nothing in the process. The audio is written in a standard, widely supported form and packaged into an MP4 that plays about everywhere. What you upload as the video is what you get back, now with a soundtrack attached.
Choose this over a full editor when you simply want to attach a track and be done. Editors are the right call if you need to fade, cut on the beat, layer several sounds, or line audio up to an exact frame. If your need is a straightforward pairing of one clip and one track, this skips all the project setup and export menus.
It suits adding narration to a screen recording, dropping a music bed under a highlight reel, replacing bad location sound with a clean studio take, and setting a still-heavy slideshow video to a song. Podcasters and course creators use it to put a voice track over simple visuals without launching heavier software.
Everything runs in your browser, so neither the video nor the audio is uploaded, there is no sign-up, and it is free. Because the work is done on your device, the only real limit is your own memory, which means very large files depend on your machine rather than any server.
The output is trimmed to the shorter of the two. Music longer than the clip gets cut where the video ends, and a video longer than the track is shortened to where the sound stops, so there is no dead air.
It attaches the audio track you provide as the clip's sound. If your video already had audio and you want the original gone, this gives you a clean single track rather than a blend of both.
No. The original video stream is kept as-is and only the audio is encoded, so the picture is not re-compressed and does not lose quality in the process.
Common audio files such as MP3, M4A, and WAV work. The tool converts the sound into a standard form inside the MP4, so the result plays consistently across devices.
This tool aligns both from the beginning and fits to the shorter one. To offset the audio, trim silence onto the front of your audio file first, or use a full editor for precise timing.
Yes. It exports as an MP4 with standard audio, which is exactly what sites like YouTube and Instagram expect, so it uploads without a conversion step.
Polished Pixels. All tools. About. Contact. Every tool runs in your browser and your files are never uploaded.