Easily Change Duration (Length) of a Clip in After Effects

This tutorial teaches you how to easily change the duration or length of a video or audio clip in After Effects.

Using Time Stretch to Change Duration of Clip in AE

In the tutorial video we have a video clip in the Composition and we want to make it longer to fit the whole composition. This is a pretty common thing you may have to do.

To begin to change the length of a clip in After Effects first activate the layer and right-click it. In the menu that appears go to Time and then Time Stretch. When we do that a box pops up. We can change this stretch factor to something greater, like 120% or to the exact duration if we know what that is.

After Effects clip menu with Time Stretch selected
Right-click layer then go to Time then Time Stretch…

The Composition in the example is 12 seconds. So type in 12 seconds. The Stretch Factor will adjust accordingly. Click OK. And now the clip stretches out to 12 seconds, or however long you set it to.

Time Stretch tool in After Effects to change length of a clip
Change the Stretch Factor or New Duration and click OK

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Using the Stretch and Duration Columns to Change Clip Length

Instead of going into the Time Stretch box, After Effects has two columns you can enable to show in the Timeline panel. Right-click on the column headings in the Timeline panel and under Columns choose Stretch or Duration.

After Effects Columns menu with Duration selected
Right-click an empty area in the Timeline Columns and under Columns choose Duration or Stretch

On the select clip(s), you can now change the length of it by clicking and dragging the value or clicking the value and typing in a new one in the Time Stretch box that’ll pop up.

Duration column in After Effects Timeline panel
Click and drag the Duration value to make the clip shorter or longer

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If you’ve read this tutorial and you still can’t figure it out, please leave a comment and I’ll do what I can to help troubleshoot it. But if you can now change the duration or length of a video or audio clip in After Effects, I hope you stick around and check out some of the other After Effects tutorials on my website or consider signing up to get notified about new blog posts and happenings around EVF.

– Josh

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