CompResizer
How to install and use CompResizer for After Effects. Presets, scaling modes, alignment, 3D reframing, and troubleshooting.
Getting Started
Requirements
- Adobe After Effects 2025 (25.0) or later
- macOS or Windows
CompResizer is a CEP extension. It installs as a panel and opens from Window → Extensions → CompResizer.
Installation
Comp Resizer is available from several stores. Follow the section for wherever you bought (or downloaded) it.
Adobe Creative Cloud Marketplace
The simplest route, Creative Cloud installs and updates it for you.
- Open the Creative Cloud desktop app.
- Go to Stock & Marketplace → Plugins and find CompResizer (or open your purchased plugins list).
- Click Install. Creative Cloud handles the rest.
- Restart After Effects if it was running, then open Window → Extensions → Comp Resizer.
Updates appear automatically in the Creative Cloud app.
aescripts + aeplugins
- Download CompResizer from your aescripts.com account (Downloads page).
- Install the aescripts + aeplugins Manager if you don't have it, then use it to install Comp Resizer. (Alternatively, install the
.zxpmanually see below.) - Restart After Effects, then open Window → Extensions → Comp Resizer.
The Manager also handles updates.
Gumroad
- After purchase, download the
.zxpfile from your Gumroad receipt email or your Gumroad Library. - Install the
.zxpmanually see Manual .zxp installation below. - Restart After Effects, then open Window → Extensions → CompResizer.
Contra
- Download the
.zxpfile delivered with your Contra purchase. - Install the
.zxpmanually see Manual .zxp installation below. - Restart After Effects, then open Window → Extensions → CompResizer.
Free trial (from aliazem.com)
- Download the trial
.zxpfrom aliazem.com. - Install it manually see Manual .zxp installation below.
- Open the panel. The header shows how many trial days remain.
- When the trial ends, the panel locks. Buy the full version from any store above and install it to keep working
The trial needs an internet connection the first time it runs.
Manual .zxp installation
Use this for Gumroad, Contra, and trial downloads or any time you have a .zxp file in hand.
- Download a free ZXP installer (for example ZXP Installer by aescripts, or ELEMENTS Media Storage's ZXP Installer).
- Open it and drag the
.zxpfile onto it. - Restart After Effects.
- Open Window → Extensions → CompResizer.
If the panel doesn't appear in the Extensions menu, quit After Effects fully (not just close the project) and reopen it.
Interface Overview
The panel is organized top to bottom in the order you'll use it:
| Section | What it does |
|---|---|
| Presets | One-click common target sizes |
| Target Size | Manual width / height, with aspect ratio lock |
| Content Scaling | Fill, Fit, or Stretch — how content adapts to the new frame |
| Alignment | 3×3 anchor grid — where content sits in the new frame |
| Options | Work on a duplicate · Adapt 3D layers |
| Resize | Runs the resize on the active composition |
CompResizer always works on the active composition the one currently open in the Timeline / selected in the Project panel.
Presets
Click a preset to instantly fill in its width and height:
| Preset | Ratio | Size |
|---|---|---|
| Vertical | 9:16 | 1080 × 1920 |
| Square | 1:1 | 1080 × 1080 |
| Portrait | 4:5 | 1080 × 1350 |
| Widescreen | 16:9 | 1920 × 1080 |
| 4K UHD | 16:9 | 3840 × 2160 |
| 720p | 16:9 | 1280 × 720 |
Selecting a preset does not resize anything by itself. It fills the Target Size fields. Click Resize to apply it.
Target Size
Enter any custom width and height in pixels (up to 30,000px per side).
Aspect Ratio Lock
When enabled, editing the width automatically recalculates a proportional height (and vice versa), based on your source composition's ratio. Turn it off to set width and height independently.
Swap
The swap button exchanges the width and height values, useful for quickly flipping between landscape and portrait versions of the same size.
Content Scaling
This controls how your existing content adapts to the new frame size.
Fill
Scales content up until it fully covers the new frame, cropping whatever overflows. Use this when you want a frame with no empty space. e.g., turning a 16:9 comp into a 9:16 story without letterboxing.
Fit
Scales content down until it fits entirely inside the new frame, adding empty space (letterboxing/pillarboxing) on the sides that don't match. Use this when nothing in the frame can be cropped.
Stretch
Scales width and height independently to exactly match the new dimensions, ignoring the original aspect ratio. This will distort circular or square elements. use only when non-uniform scaling is intentional.
Alignment
The 3×3 grid sets the anchor point used by Fill and Fit. i.e., which part of your original frame stays visible and which part is more likely to be cropped or padded.
For example, with Fill and top-center alignment, content is scaled to cover the new frame while keeping the top of the original frame in view and cropping evenly from the sides and bottom.
Alignment has no effect in Stretch mode, since nothing is cropped or padded.
Options
Work on a Duplicate
When enabled, Comp Resizer duplicates the active composition and resizes the copy, leaving your original untouched. The duplicate is named <original name> <width>x<height> and opens automatically. Turn this off to resize the composition in place.
Adapt 3D layers (Experimental)
CompResizer's 2D engine handles the vast majority of compositions, including 3D layers used for simple depth or camera moves, without this option. Enable Adapt 3D layers when your comp contains 3D layers that need to reframe along with everything else.
How it works
If your comp has 3D layers but no camera of its own, CompResizer adds a camera that replicates the default view before resizing, then adjusts that camera's zoom to match the new frame your 3D layers themselves are never modified, precomposed, or nested. If your comp already has a camera, its zoom is adjusted the same way.
Experimental feature complex 3D scenes may not reframe as expected. Always review your 3D layers after resizing.
How Resizing Works
Every resize runs inside a single undo group. If anything looks wrong, press Cmd/Ctrl + Z once to fully revert — nothing is left behind.
CompResizer does not bake, precompose, or flatten your layers (2D or 3D). It temporarily parents layers to a rig, applies the new scale and position, then releases the rig your layer structure, effects, and keyframes stay exactly as they were, just repositioned and rescaled.
Troubleshooting
The panel is blank or won't open
Restart After Effects fully (quit the app, don't just close the project). If it persists, reinstall the extension the same way you installed it.
Comp Resizer isn't in the Extensions menu after installing
Quit After Effects completely and reopen it. The Extensions menu is only read at startup. If it's still missing, reinstall the .zxp and make sure the installer reported success.
"Engine not loaded — reopen the panel"
This can happen on the very first action after AE starts. Close and reopen the panel from Window → Extensions, then try again.
"Select or open a composition first"
Comp Resizer needs an active composition open one in the Timeline, or select one in the Project panel.
Nothing happens when I click Resize
Check the status line under the button. It reports the exact reason (invalid size, no composition, etc.). If the target size matches the current size, there's nothing to resize.
3D layers look wrong after resizing
Make sure Adapt 3D layers is enabled before resizing. If it's already on and results still look off, this is a known limitation of the experimental 3D engine. Please report the scenario so it can be improved.
The trial says it's expired but I just installed it
Trial time is counted per machine, from the first launch reinstalling doesn't
reset it. If you believe this is wrong, contact support from the Settings → Support tab.
The trial won't start / can't check status
The trial needs an internet connection on first launch. Check your connection (or firewall) and reopen the panel.
FAQ
Will this move my keyframed animations?
Yes. Reframing repositions the entire layer stack, including anything animated, based on the alignment and scaling mode you choose.
Do I need to rig or prepare my comp first?
No. There's nothing to set up. Open any comp even an old one and resize.
Is it a subscription?
No. Comp Resizer is a one time purchase. The version you buy keeps working forever, with no recurring bill.
Do I pay again for future versions?
Updates within your version (v1.1, v1.2, and so on) are free. Major new versions like v2 add significant new features and are optional paid upgrades and as an existing customer, you get discounted upgrade pricing through aescripts. Whatever version you own keeps working regardless.
Does it work with 3D layers?
2D layers are fully supported. For 3D layers, you can currently resize using an experimental method. Since this feature is still in the testing phase, we recommend checking the result at the new size.
Can I resize multiple compositions at once?
Not yet. Comp Resizer works on one active composition per run. Batch reframing is on the roadmap.
Can I resize pre-comps?
Partially yes. You can open your pre-comp and resize it on its own. However, there is no feature to automatically rescale pre-comps within the main composition. That feature is in the roadmap.
Can I undo a resize?
Yes. Every resize is wrapped in a single undo step.
Which After Effects versions are supported?
AE 2025 (25.0) and newer, on macOS and Windows. Work is ongoing to improve support for older After Effects versions.
How many machines can I activate?
A Single User License activates on 2 machines, managed from your aescripts.com account.
Version History
1.0.0
Initial release. Presets, Fill/Fit/Stretch, alignment, duplicate-safe mode, experimental camera-based 3D reframing.
Support
Found a bug or have a feature request? Send email to toolsupport@aliazem.com include your After Effects version, OS, and a short description of what you were resizing.