How to add, edit and bake expressions in After Effects

How do I add an expression in After Effects?

You either apply a ready expression from a panel or type your own into the property. This page gives full steps for the panel route, because that is the one we could check line by line. We make mouzeclick, so read the panel steps with that in mind.

mouzeexpr is one of the 15 After Effects extensions in mouzeclick. It holds 24 ready expressions, each with its own settings, sorted into five groups. You choose one, set the numbers, and the panel applies it. Afterwards the same panel updates the settings, removes the expression or bakes it to keyframes, so you don't have to dig back into code to change a value.

Add an expression with mouzeexpr

1. Install mouzeclick and paste your key. The key email has the Windows and Mac download links, and they are also on your account page.
2. In the mouzeclick app, open the Tool wheel page and press Install After Effects bridge. You do this once.
3. Restart After Effects.
4. Open mouzeexpr from Window › Extensions.
5. Select the property you want to drive.
6. Pick one of the 24 expressions from its group and set its options.
7. Press Apply.
8. Play or scrub the comp. If the motion needs changing, edit the settings and press Update.

Keep mouzeclick running while you work: the panels rely on the app, and updates refresh them by themselves. All 24 expressions and their options are on the mouzeexpr feature page, which lists 34 items in the feature library.

How do I open expressions in After Effects and type my own?

You type your own expression into the property's expression field. Adobe documents how to open that field in its own help, and that is where to take the exact steps from. We haven't reproduced Adobe's menu paths or shortcuts on this page, because we could not verify them against Adobe's text on 3 November 2026.

Keep two references open while you write code:

• Adobe's expression language reference, the maker's own documentation.
• The After Effects expressions documentation at docsforadobe.

For the snippets people ask for most, we have separate guides to the wiggle expression, the loopOut expression and the inertial bounce expression.

If you paste the same few lines again and again, store them once. An Options wheel slot or a macro can type text for you, and mouzerun can hold an expression as a button. Both are covered in the shortcut section below.

Which mouzeclick tools add expressions, and where do they run?

Six parts of mouzeclick touch expressions. Four run on Windows and Mac; the two inside the After Effects workspace are Windows only. Checked on 3 November 2026.

The workspaces are part of mouzeclick on Windows. The Mac app does not include them. Everything else in the table works the same on both systems with the same key.

How do I add an expression to Position in After Effects?

Select the layer's Position property, pick a ready expression in mouzeexpr, set its numbers and press Apply. Position is a property like any other, so the steps are the ones above. The feature page lists all 24 expressions and their settings, so check which one fits the move you want.

1. Park the layer where it should sit before the expression runs, so you are judging the expression and not a stray keyframe.
2. Select Position in the timeline.
3. In mouzeexpr, pick the expression and set its options. Start with small values and raise them while you watch the comp play.
4. Press Apply, then play a few seconds at full frame rate. Scrubbing hides problems that real playback shows.
5. Adjust and press Update until it reads right.
6. When the motion is signed off, press Bake to keyframes if you want ordinary keys you can nudge one at a time.

If you would rather type the code, start with the wiggle and loop guides linked above.

Often what people want on Position is a camera feel rather than code. Two mouzeclick tools give you one without an expression to manage:

• Motion lab in the After Effects workspace has 14 camera shakes and flickers. Click to preview, double-click to apply, then set Speed, Strength and a flash. Windows only.
• mouzecam, an extension for Windows and Mac, is a camera rig with handheld drift, parallax, focus and rack focus. Its moves include Push in, Orbit and Whip pan.

How do I change or remove an expression once it's applied?

In mouzeexpr, change the expression's settings and press Update; to take it off, press Remove. You don't have to open the code to change a value the panel set.

This matters most on long projects. A client asks for a gentler move three rounds later, and the change is one number and one press rather than a hunt through code on a dozen layers. Keep these habits:

• Update while you are still deciding. The expression stays live and editable.
• Remove when you no longer want it. The expression and the motion it made both go.
• Bake when the motion is final. That is covered in the next section.

If you wrote the expression yourself, edit it in the property's expression field, with Adobe's reference to hand. For your own code, mouzerun is the better home, because it keeps the expression as a button you can apply again.

How do I bake an expression to keyframes in After Effects?

In mouzeexpr, select the property and press Bake to keyframes. The expression's motion is written out as ordinary keyframes, so the result no longer depends on the code or on the panel.

Bake when one of these is true:

• You want to hand-tweak a single moment, such as one frame of a shake, without touching the rest.
• You are sending the project to someone who doesn't have mouzeclick, and you want them to see keys rather than an expression they can't adjust from a panel.
• You want to retime the motion with keyframe tools rather than with expression settings.

On Windows, the After Effects workspace's Toolbox also has four keyframe utilities: Reverse, Loop dup, Reposition and Smart bake.

Remove and Bake are different on purpose. Remove throws the motion away. Bake keeps the motion and drops the code. If you are not sure, bake: keyframes can always be deleted, and you can apply the expression again from mouzeexpr.

Is there an After Effects expression shortcut, and can it go on a mouse?

Adobe lists its shortcuts in its own help. We could not verify the expression shortcuts against it on 3 November 2026, so none are quoted here. Our After Effects keyboard shortcuts list and the guide to changing keyboard shortcuts in After Effects cover the keyboard side. mouzeclick adds three ways to make expressions one press.

Make your expression a button with mouzerun

mouzerun is a panel of your own one-click buttons. Each button is one of five kinds: a script, an expression, an animation preset, a menu command or a keyframe ease. Save the expression you use on every job as a button and apply it from the panel. It comes with six starter buttons, and you can export your buttons and import them again. Windows and Mac.

Put the shortcut on a mouse button

The mouzeclick mouse app puts shortcuts on the buttons of any mouse your computer sees, per app. Mouse 4 can do one thing in After Effects and something else in Chrome, and it changes the moment you switch windows. Each button has eleven slots: tap, hold and move in four directions, a chord with another button, or hold and scroll. The library holds 309 built-in shortcuts on Windows, 44 of them for After Effects. A hotkey or macro you make sits beside them. Windows and Mac.

Park snippets on the Options wheel

The Options wheel opens with F8, Ctrl + right click or a side button. It holds 48 favourites per app on three rings of 12, 16 and 20. A slot can hold keys, a macro or typed text, so with the expression field open you pick the slot and the snippet is typed in. If a snippet needs a few steps around it, a macro can chain keys, clicks, waits, typed text and launches. Windows and Mac; on a MacBook keyboard the wheels use Fn + F8 and Fn + F9.

Where can I find ready-made After Effects expressions?

Inside mouzeclick there are three sets: mouzeexpr's 24 on Windows and Mac, the workspace Library's 25 on Windows, and the expressions built into mouzekit's tools. Our After Effects expressions library guide walks through them side by side.

• mouzeexpr. 24 ready expressions in five groups, each with settings, each removable or bakeable. The best start if you want control without code.
• The workspace Library. 25 recommended expressions, stored next to Comp Saver, FFX presets and an asset library shared with the Premiere Pro workspace. It is part of the After Effects workspace, which is Windows only.
• Easing lab. Also in the workspace, so also Windows only. It has six curve types (Bezier, Spline, Elastic, Bounce, Wave and Steps) and 44 ready curves. Any curve can be copied as an expression, which is handy when you want an elastic or bounce feel written as code you can paste.
• mouzekit. 28 After Effects tools in 7 groups: Rigs, Properties, Layers and time, Looks, Text, Tidy and Make. Its expressions work in any language of After Effects, and each tool is one undo step.

If none of these is the expression you need, write it once, test it, then save it as a mouzerun button so it is ready on the next job.

What should I check when mouzeexpr doesn't show up or won't apply?

Most problems come from the bridge not being installed, After Effects not being restarted, or mouzeclick not running. Work through this list in order.

1. Is mouzeclick running? Look for its icon in the tray on Windows or the menu bar on Mac. The panels need the app, and the app needs an internet connection while it runs, because the licence and profiles live in your account.
2. Is the bridge installed? In the app, open the Tool wheel page and press Install After Effects bridge, then restart After Effects. One bridge panel serves Premiere Pro and After Effects at once.
3. Are you looking in the right menu? mouzeexpr is an extension, a panel under Window › Extensions. It is not an effect plug-in, so it won't appear in the effects list. Our guide to plugins, scripts and extensions explains why a panel can go missing.
4. Is a property selected? Select the property you want to drive before you press Apply.
5. On a Mac, did you allow the app? Apple has not notarized the Mac app yet. Allow it once under System Settings › Privacy & Security › Security › Open Anyway. Then turn mouzeclick on under Accessibility and Input Monitoring, quit it and open it again. The four steps are on the Mac install page.
6. Is your After Effects version a problem? mouzeclick publishes no minimum After Effects version. Try it in your version during the 3-day trial before you pay.

If it still won't apply, email [email protected]. Priority email support comes with every key.

What do you need before you start?

You need After Effects itself. For the panel route you also need mouzeclick on Windows 10 or 11, or macOS 12 or newer on Apple Silicon or Intel.

After Effects is sold only as part of a Creative Cloud membership. As shown on Adobe's pages on 3 November 2026, the single app costs US$22.99/mo on the Annual, billed monthly plan, and ₹733.96/mo incl. GST in India, annual, billed monthly. Adobe's free trial runs on macOS, iPadOS and Windows, and you have 14 days after the trial ends to cancel for a full refund.

mouzeclick is one plan with everything included: the mouse app and its three wheels, every After Effects extension and every Premiere Pro tool, and both workspaces on Windows. It costs $25 a month, $249 a year, or $499 once for one of the first 100 lifetime keys. The trial is 3 days with no card, and every After Effects tool works fully during it. See mouzeclick pricing for how to pay.

Where mouzeclick fits (we make it)

If you write expressions every day and know the language well, you may not need a panel at all; Adobe's reference and a text file of snippets go a long way. mouzeclick earns its place in three cases.

• You want common expressions with settings you can change later, and a clean bake when the motion is final. That is mouzeexpr.
• You reuse your own code across jobs. mouzerun stores it as buttons you can export, and the Options wheel types it for you.
• You want expression-related actions on your mouse, per app, without vendor software or a driver.

All of that runs on Windows and Mac. The workspace extras (the Library's 25 expressions, Easing lab and Smart bake) are Windows only. Every extension is listed on the extensions page, with the setup steps.

Questions people ask

Sources

Checked on 2026-11-03. Prices and features change: each link goes to the maker's own page.

1. Adobe: After Effects product page and single-app price (checked 3 Nov 2026)
2. Adobe: Creative Cloud plans, India price (checked 3 Nov 2026)
3. Adobe: After Effects free trial, platforms and refund window
4. Adobe: After Effects expression language reference
5. After Effects expressions documentation (docsforadobe)

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