Filmora - AI Video Editor
Edit Faster, Smarter and Easier!

Think Bigger From Filmora User Guide

Preview Render Files

Preview rendering reduces the preview lag which can occur when editing complex or high-resolution projects.

This results in smoother playback. Filmora offers 2 ways to render your timeline preview:

Manual Render (Render Preview)

Click the Render Button to begin rendering your timeline whenever this red line appears (as when you add media or make other changes to your timeline).

render files

The render preview window will pop up, showing the render progress and the estimated remaining time.

render files

Once the rendering is complete, the red line will turn green.

You will need to wait until the rendering process is finished to continue editing.


Besides manually clicking the Render Button, you can also use a feature called Background Render. If you enable it, your videos will be rendered automatically when you add your videos to the timeline for editing.

You can go to File-Preferences-Performance, set a starting time, and enable it.

By default, the render process will be performed after 5 seconds of inactivity on the timeline.

render files

Click OK to save your settings.

The rendered parts of your timeline will be indicated by a green line. The line will be red for the un-rendered parts. Once you change, modify, or add effects to the rendered section you’ll notice the line turning red to indicate you need to render again.