🎢CSS Cubic-Bezier & Animation Easing Generator Documentation & Guide

CSS & Design

Cubic Bézier curves define the mathematical acceleration rate of CSS transitions and keyframe animations along a continuous time-progression vector. By parameterizing two off-curve control points \(P_1(x_1, y_1)\) and \(P_2(x_2, y_2)\), developers craft organic physical responses—such as snappy UI feedback, bouncy spring overshoots, and decelerated easing—that standard linear or keyword presets cannot replicate.

📋How to Use This Tool

Select a Preset Easing: Click any preset chip (e.g. Snappy Spring, Elastic Overshoot, or Ease-Out) to load production-tested control curves.
Tweak Control Points: Fine-tune coordinates \(x_1, y_1, x_2, y_2\) using the interactive sliders. Note that \(y\) coordinates can exceed \(1.0\) to create bounce and elastic spring rebounds.
Preview Motion: Watch the simulated runner compare linear progression side-by-side with your custom easing curve in real time. Adjust duration as needed.
Export CSS & Tailwind: Click 🎢 Generate Easing CSS to compile standard CSS, Tailwind CSS arbitrary classes, and Web Animations API code.

⚙️The Bernstein Polynomial & Coordinate Constraints

CSS timing functions evaluate a third-order parametric Bézier curve between fixed anchors \(P_0(0, 0)\) and \(P_3(1, 1)\):

• Parametric Formula: \(B(t) = (1-t)^3 P_0 + 3(1-t)^2 t P_1 + 3(1-t) t^2 P_2 + t^3 P_3\) for \(t \in [0, 1]\).

• Strict X Constraints: The time axis \(x\) strictly requires \(0 \le x_1, x_2 \le 1\). Time cannot flow backwards in physical rendering.

• Unbounded Y Dimension: The progress axis \(y\) permits values below \(0\) (anticipation) and above \(1.0\) (overshoot rebounds).

• Perceptual Spring: Values like cubic-bezier(0.34, 1.56, 0.64, 1) produce lightweight zero-runtime physics without heavy JavaScript spring engines.

💡Practical Use Cases & Best Practices

Interactive Button Presses: Use snappy curves with fast durations (150ms–200ms) for hover states and active button depresses.
Modal Entrance & Drawer Sheets: Pair ease-out or spring overshoot on drawer entrances, and switch to high-speed ease-in on dismissal to ensure UI responsiveness.
Avoid Linear for Physical Objects: Linear motion looks robotic and unnatural for spatial movement; reserve linear for continuous background loops and color fades.

100% Client-Side Privacy Guarantee:All Bézier math, parametric evaluations, and keyframe generation execute exclusively in your local browser sandbox. Zero stylesheet tokens or animation parameters are transmitted over external networks.

CSS Cubic-Bezier & Animation Easing Generator