Loop a video with music

With Until the music ends selected, the song decides the running time. If you trim the track to 2 minutes 40 seconds, the video is 2 minutes 40 seconds long, however short the loop is. The clip plays as many full passes as fit, and the final pass stops wherever the music does.

That last pass will usually end part-way through, so a Fade out on the music is worth adding: the ending then sounds deliberate even though the picture stops mid-loop. The join settings still apply to every pass in between, so a Crossfade or Blend behaves exactly as it would with any other repeat mode.

Exports are capped at three hours. A single song is far shorter than that, but a long DJ mix or an album joined into one file can go past it.

There is no speed control, so the loop can’t be stretched or squeezed to fit a tempo. What you can do is choose its length. Because the handles are frame-accurate, you can set the loop to a whole number of beats and let each pass land on the music in the same place.

• Find the tempo of the song in beats per minute; many music apps and sheet music list it.
• Divide 60 by the tempo to get one beat in seconds. At 120 BPM a beat is 0.5 seconds, so a four-beat bar lasts 2 seconds.
• Set Loop start and Loop end so the loop lasts one or two bars. Arrow keys move a handle one frame, and Shift with an arrow moves it one second.
• If you use a Crossfade, remember that each pass gets shorter by the crossfade length, because the end dissolves into the start. Add that amount to the loop when you set the handles.

Use Music start to trim any silence or count-in from the front of the track, so the first downbeat lines up with the first frame. Even when a loop isn’t locked to the beat, slow, even movement such as water or traffic rarely clashes with music.

Sometimes the length matters more than the track: a ten-minute slot, or an hour of background picture for a stream or a shop screen. Choose Length instead, pick a duration or type a Custom length, set the sound to Music, and turn on Repeat the music so the song starts again whenever it runs out.

For very long files, the one-hour loop page explains how the export stays quick and what decides the file size. If you only need a clip to reach a set running time, see make a video longer.

The Sound setting has three choices, and only one plays at a time.

• Original keeps the clip’s audio. Smooth the sound at the join (on by default) blends the last moment of sound into the first so each repeat doesn’t click.
• Music plays your chosen track and drops the clip’s audio completely.
• Off exports a silent video, for example when you will add audio in another app.

If you need speech from the clip with a song quietly underneath, export the loop here with the original sound, then mix in the music using a timeline editor. loop.video does not mix the two.

Owning a copy of a song, whether bought or downloaded, doesn’t usually give you the right to publish it in a video. Video and social platforms check uploads for recorded music, and a match can mean the sound is muted, the video is blocked in some countries, or the earnings go to the rights holder.

Safer choices

• Music you made yourself, or recorded with permission.
• Tracks from a royalty-free or stock music library, used within the licence terms. Keep a copy of the licence in case a claim appears later.
• Music provided inside the platform you are posting to, added there rather than in the file.

For private use, such as a loop for your own TV or a party screen, none of this applies in the same way, but check the rules before playing music in a shop or other public space.