An AET file is primarily an Adobe After Effects template project, functioning as a reusable starter setup similar to an AEP but meant to be opened repeatedly without overwriting the original, so After Effects treats it like a master you open and then save as a new project, containing the full "recipe" for the animation—comps, timelines, layer stacks, keyframes, effects, expressions, cameras/lights, render settings, and organizational elements like folders and interpretations.

In case you have any concerns with regards to exactly where in addition to how you can use universal AET file viewer, you can email us with our own web site. An AET normally doesn’t pack raw assets, instead storing references or paths to external audio, images, and video, which is why template sets are bundled as ZIPs with Footage/assets folders and why After Effects reports missing items if things were moved, and because AETs might rely on certain fonts or plugins, opening them elsewhere can trigger alerts until everything is installed, and since file extensions aren’t exclusive, checking "Opens with" or the file’s source location is the best way to confirm the program behind it and what extra files should accompany it.

An AEP file is the standard AE project where you build and edit animations, updated as you import footage, adjust comps, and refine effects, while an AET is a template meant as a reusable starting point, so the practical difference is workflow: you reopen an AEP to keep editing the same project, but you open an AET to create a new project so the template stays untouched.

That’s why AETs are commonly chosen for packaged motion-graphics templates such as intros, lower-thirds, and slideshows: the creator keeps the AET as the master and each time a new video is needed you open it, immediately Save As a new project (becoming your own AEP), then swap text, colors, logos, and media, and although both formats can store the same project elements—comps, layers, keyframes, effects, expressions, cameras/lights, and settings—and both usually reference external footage, the AET is built to protect the master for repeatable work while the AEP serves as the editable file you keep updating.

An AET file stores the structural and behavioral setup of an After Effects project without always embedding media, including compositions with their resolution, frame rate, duration, and nesting, alongside the full timeline build of layers like text, shapes, solids, adjustment layers, precomps, and placeholders, each with properties such as position, scale, rotation, opacity, masks, mattes, blending modes, and parenting, plus animation data like keyframes, easing, markers, and any expressions that automate movement.

On top of that, the template remembers all effects and their settings—color correction, blurs, glows, distortions, transitions, and more—along with any 3D setup such as cameras, lights, 3D layer properties, and render/preview settings, plus project-level organization like folders, label colors, interpretation rules, and sometimes proxies, but it typically does not bundle full footage, images, audio, fonts, or plugins, instead keeping links and dependencies that may trigger missing-asset or missing-plugin warnings on another computer until everything is relinked or installed.