How to add music to an HTML animation video

Choose an audio mode

Mute creates a silent video. Replace audio mutes the source and uses your local file. Keep original audio preserves a shared tab-audio track. Mix audio combines that track with a local file and lets you adjust each volume separately.

Canvas capture has no audio track. Keep and Mix are therefore available only through tab recording, and the export checks that the browser actually supplies audio. Browser and operating-system support varies.

Trim and place your soundtrack

1. Import your HTML animation, set the video duration, and select Replace audio.
2. Choose a local MP3, WAV, M4A, OGG, or FLAC file. Your browser must be able to decode it; the extension alone does not guarantee support.
3. Set Trim start and Trim end to choose the part of the track you want.
4. Set Start in video to delay the track. For example, 0.3 starts the added audio 300 milliseconds into the video.
5. Set volume and Fade in/Fade out. Enable Loop audio until the video ends if the trimmed section is shorter than your video.
6. Use Preview audio + animation, then export and listen to the resulting video.

A practical timing example

For a 15-second video, trim a local track from 2 to 7 seconds, start it at 0.3 seconds, and enable looping. The five-second segment repeats after the initial delay and is clipped at the video end. A 0.5-second fade-in eases the start; a 1-second fade-out softens the ending.

If looping is off, the five-second segment finishes at 5.3 seconds and the remaining video is silent. These settings describe the added audio, not a beat-synchronization feature.

Check the exported timing

Capture is real time, so arbitrary HTML may not start at a perfectly deterministic point. Native AAC priming is calibrated locally and compensated in MP4 output; encoder padding may still slightly extend the file. A controlled offset/fade fixture was measured within one frame at 30 FPS, which is not a guarantee for all sources.

If your file will not decode, try a WAV version you have the right to use. The converter does not download music from YouTube or Spotify and does not bypass DRM. Choose audio you are allowed to include in your video.

A real canvas export

This four-second silent MP4 was created with this converter from the downloadable canvas sample at 720 × 1280. Try the same source before importing your own animation.

Questions before you start