How to make a dynamic text box in After Effects

In this After Effects tutorial, we create a responsive box behind text using just the text layer itself. No shape layers are needed. Perfect for quick and easy social media caption overlays.

Easy Dynamic Text Box After Effects HD

Step 1: Add a Fill effect

Add a Generate > Fill effect and choose your box color.

Step 2: Add a Shift Channels effect

Add a Channel > Shift Channels effect. Change ‘Take Alpha From’ to ‘Full On’.

Step 3: Add a CC RepeTile effect

Add a Stylize > CC RepeTile effect. Change all values to 40. This is the padding of your box so feel free to increase these values.

Step 4: Add a CC Composite effect

Add a Channel > CC Composite effect. This will make your original text visible again.

Step 5: Add 2 Simple Choker effects

For rounded corners add two Matte > Simple Choker effects. Use values of 15, and negative 15. These values represent the ’rounding’ of the box and should be adjusted together, though the second value should be a negative of the first.

That’s it! The box will automatically resize and move as you edit and position your text.


Quick Tip: You can use expression sliders for the CC RepeTile and Simple Choker values, which will control the box ‘padding’ and ’roundness’ respectively. Remember to make the second Simple Choker value a negative value of the first.