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---
name: timing
description: Interpolation and timing in Remotion—prefer interpolate with Bézier easing; springs as a specialized option
metadata:
tags: easing, bezier, interpolation, spring, timing
---
Drive motion with `interpolate()` over explicit frame range. To customize timing, use **`Easing.bezier`**. The four parameters are the same as CSS `cubic-bezier(x1, y1, x2, y2)`.
A simple linear interpolation is done using the `interpolate` function.
```ts title="Going from 0 to 1 over 100 frames"
import { interpolate } from "remotion";
const opacity = interpolate(frame, [0, 100], [0, 1]);
```
By default, the values are not clamped, so the value can go outside the range [0, 1].
Here is how they can be clamped:
```ts title="Going from 0 to 1 over 100 frames with extrapolation"
const opacity = interpolate(frame, [0, 100], [0, 1], {
extrapolateRight: "clamp",
extrapolateLeft: "clamp",
});
```
## Bézier easing
Use `Easing.bezier(x1, y1, x2, y2)` inside the `interpolate` options object. The curve is identical in spirit to CSS animations and transitions, which helps when you are stealing timing from the web or from a designers spec.
```ts
import { interpolate, Easing } from "remotion";
const opacity = interpolate(frame, [0, 60], [0, 1], {
easing: Easing.bezier(0.16, 1, 0.3, 1),
extrapolateLeft: "clamp",
extrapolateRight: "clamp",
});
```
### Examples (copy-paste curves)
**1. Crisp UI entrance (strong ease-out, no overshoot)** — slows nicely into the rest value; similar to many system “deceleration” curves.
```tsx
const enter = interpolate(frame, [0, 45], [0, 1], {
easing: Easing.bezier(0.16, 1, 0.3, 1),
extrapolateLeft: "clamp",
extrapolateRight: "clamp",
});
```
**2. Editorial / slow fade (balanced ease-in-out)** — symmetric acceleration and deceleration over a hold-friendly move.
```tsx
const progress = interpolate(frame, [0, 90], [0, 1], {
easing: Easing.bezier(0.45, 0, 0.55, 1),
extrapolateLeft: "clamp",
extrapolateRight: "clamp",
});
```
**3. Playful overshoot (control point y > 1)** — a little past the target then settles; use sparingly for emphasis.
```tsx
const pop = interpolate(frame, [0, 30], [0, 1], {
easing: Easing.bezier(0.34, 1.56, 0.64, 1),
extrapolateLeft: "clamp",
extrapolateRight: "clamp",
});
```
## Preset easings (`Easing.in` / `Easing.out` / named curves)
Easing can be added to the `interpolate` function without a custom cubic:
```ts
import { interpolate, Easing } from "remotion";
const value1 = interpolate(frame, [0, 100], [0, 1], {
easing: Easing.inOut(Easing.cubic),
extrapolateLeft: "clamp",
extrapolateRight: "clamp",
});
```
The default easing is `Easing.linear`.
Convexities:
- `Easing.in` — starting slow and accelerating
- `Easing.out` — starting fast and slowing down
- `Easing.inOut`
Named curves (from most linear to most curved):
- `Easing.quad`
- `Easing.cubic` (good default when you do not need a custom cubic)
- `Easing.sin`
- `Easing.exp`
- `Easing.circle`
### Easing direction for enter/exit animations
Use `Easing.out` for enter animations (starts fast, decelerates into place) and `Easing.in` for exit animations (starts slow, accelerates away). This feels natural because elements arrive with momentum and leave with gravity. When you need a specific curve from design, prefer a single `Easing.bezier(...)` instead of stacking presets.
## Composing interpolations
When multiple properties share the same timing (e.g. a slide-in panel and a video shift), avoid duplicating the full interpolation for each property. Instead, create a single normalized progress value (0 to 1) and derive each property from it:
```tsx
const slideIn = interpolate(
frame,
[slideInStart, slideInStart + slideInDuration],
[0, 1],
{
easing: Easing.bezier(0.22, 1, 0.36, 1),
extrapolateLeft: "clamp",
extrapolateRight: "clamp",
},
);
const slideOut = interpolate(
frame,
[slideOutStart, slideOutStart + slideOutDuration],
[0, 1],
{ easing: Easing.in(Easing.cubic), extrapolateLeft: "clamp", extrapolateRight: "clamp" },
);
const progress = slideIn - slideOut;
// Derive multiple properties from the same progress
const overlayX = interpolate(progress, [0, 1], [100, 0]);
const videoX = interpolate(progress, [0, 1], [0, -20]);
const opacity = interpolate(progress, [0, 1], [0, 1]);
```
The key idea: separate **timing** (when and how fast) from **mapping** (what values to animate between).