What is the AEP file format?
.aep files are used by the video and graphics editing and post-production software Adobe After Effects. An .aep file contains a video project and its related data, including audio, video and image references, the composition timeline, transitions and other effects. It stores references to source assets rather than rendered footage.
.aep stores data in binary format using a big-endian RIFF container, identified by the four-byte signature RIFX at offset 0. After Effects uses .aep as its default project format. The .aepx format, which is based on XML and stores project data as plain text, is also supported.
Security & safety
RISK: MEDIUMAn AEP is project data, but After Effects supports scripting (Expressions/scripts), and downloaded templates can ship with .jsx scripts or 'script-driven' setups - only run AE scripts from templates you trust. The bigger practical pitfalls: pirated 'free AEP template' sites bundle malware in the download archives, and projects often arrive with missing footage (relink the assets). Get After Effects only from Adobe, and templates from reputable marketplaces.
Format details
in a nutshellFULL NAMEAdobe After Effects Project
DEVELOPERAdobe Inc.since 1993 (After Effects 1.0; CoSA/Adobe)
CATEGORYVideo Files
MIME TYPEapplication/octet-stream
TYPEBinary project file (references to assets; not rendered video)
MAGIC BYTES · FILE SIGNATURE
OFFSET
00010203
HEX
52494658
ASCII
RIFX
An .aep is a big-endian RIFF file: it begins with "RIFX" (52 49 46 58) at offset 0, with the form-type "Egg!" following the size field. (The XML-based variant .aepx is a plain-text alternative that starts with an XML declaration.)
Programs that open AEP files
Windows1 app
Adobe After Effects
Paid Open the .aep with After Effects (Creative Cloud). It's the only app that reads the project. Relink any 'missing' footage when prompted. 
macOS1 app
Adobe After Effects
Paid Open the .aep in After Effects for macOS (Creative Cloud); same project format across Windows and Mac. Technical details
deep spec| Container | Big-endian RIFF variant (RIFX); not the standard little-endian RIFF used by most Windows media files |
| Magic bytes | 52 49 46 58 ("RIFX") at offset 0; form-type "Egg!" follows the size field |
| MIME type | application/octet-stream |
| Encoding | Proprietary binary; not human-readable |
| Content model | Project file - stores composition metadata and references to external source assets, not encoded video |
| Asset references | Links to external footage, audio and image files by absolute or relative file path; relocating assets breaks the link |
| Compositions | Holds one or more named compositions, each with a layer stack, timing, keyframes and effects |
| Expressions | Supports JavaScript-based expressions for procedural property animation on any keyframeable parameter |
| Platform | Cross-platform; identical binary file format on Windows and macOS |
| Version compatibility | Backward-incompatible: projects saved in a newer version of After Effects cannot be opened in older versions |
| XML variant | .aepx is the plain-text XML counterpart; functionally equivalent but human-readable and diff-friendly |
| Auto-save copies | After Effects writes incremental auto-save copies (also .aep) to an Auto-Save subfolder alongside the project |
| Related templates | .aet (After Effects template), .mogrt (Motion Graphics Template exportable to Premiere Pro) |
| Released | 1993 (After Effects 1.0; CoSA/Adobe) |
| Specification | helpx.adobe.com |
AEP conversions
Possible
.AEP .MOVGUIDE
Yes -- open the project in Adobe After Effects, add the composition to the Render Queue with a QuickTime/MOV…
How to convert
.AEP .MP3GUIDE
Yes, you can get an MP3 from an AEP, but only by rendering the audio out of After Effects - there is no…
How to convert
.AEP .MP4GUIDE
Yes, you can get an MP4 from an AEP file - but the correct term is "render," not convert. Open the project in…
How to convert
.AEP .GIFGUIDE
Yes - the fastest way is to render the composition directly to an animated GIF via Adobe Media Encoder from…
How to convert
.AEP .AEPXGUIDE
Yes, After Effects converts AEP to AEPX in one step via File > Save As > Save a Copy as XML (.aepx).
How to convert
.AEP .MOGRTGUIDE
Yes -- the only way to do this is inside Adobe After Effects: open the composition, set up Essential Graphics…
How to convert
.AEP .JPGGUIDE
Yes - use After Effects to save a single frame as JPEG (Composition > Save Frame As > File).
How to convert
.AEP .PNGGUIDE
Yes, you can get a PNG from an AEP file - the only way is to render it in Adobe After Effects, either as a…
How to convert
Not possible
Community Q&A
asked by usersNo questions yet - be the first to ask about AEP files.
Frequently asked questions
How do I open an AEP file?
Only with Adobe After Effects (Creative Cloud, paid). There is no free standalone AEP viewer because the file is an editable project that has to be rendered to be seen. If you just need the result, ask the sender to export an MP4/MOV.
How do I convert an AEP to MP4?
You render it, not convert it. Open the .aep in After Effects, add the composition to the Render Queue (or Adobe Media Encoder) and export to MP4 (H.264). No tool can do this without After Effects and the project's linked footage.
Why is my footage 'missing' when I open an AEP?
An .aep only stores links to source files, not the media itself. If those files aren't on your system at the expected paths, After Effects marks them missing - relink them, or ask the sender to use File > Dependencies > Collect Files to package everything.
Can I open an AEP without After Effects?
No. There's no other app that reads .aep, and you can't 'preview' a project without rendering it. Free trial of After Effects, or ask for a rendered video, are the only options.
Why won't my AEP open in my version of After Effects?
Projects aren't forward-compatible - an .aep saved in a newer After Effects won't open in an older one. Ask the sender to do File > Save As > Save a Copy As (previous version) for the version you have.
What's the difference between AEP and AEPX?
Same After Effects project, different encoding: .aep is binary, .aepx is the project saved as XML (text). Both open in After Effects; AEPX is occasionally used for scripting/version control.
References
1Adobe - After Effects projects and compositionshelpx.adobe.com
2Adobe - Collect files / manage dependencieshelpx.adobe.com
