Bézier Curve Playground
Bézier curves are the smooth curves behind vector graphics, fonts and animation easing. This playground lets you drag the control points of a quadratic, cubic or higher-order Bézier and see the curve update live, with an animated construction that shows De Casteljau’s algorithm folding the control polygon down to the single point that traces the curve as the parameter t sweeps from 0 to 1. Toggle the construction lines, scrub t by hand, and read off the Bernstein blending weights that mix the control points.
Runs 100% in your browser — simulations are computed locally on your device.
Read the full guide to this tool
Notes
- De Casteljau’s algorithm repeatedly takes linear interpolations between neighbouring points; the last point left is the curve position at that t.
- The curve is a weighted blend of the control points using Bernstein polynomials, so it always stays inside their convex hull.
- The curve is tangent to the control polygon at its ends, which is why moving an endpoint handle steers the starting direction.
- Runs 100% in your browser — simulations are computed locally on your device.
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