Input
A d string, an <svg> fragment, or a dropped file. Groups and transforms are flattened. Subpaths are kept in order.
What this does
Corner rounding is normally a circular arc: at the joint the curvature jumps from zero to 1/r instantly. This rebuilds the path so curvature — and its rate of change — stay continuous through every joint.
a demo is running — paste your own path to replace it
Quality
Subpaths—
Length vs original—
Peak curvature—
Turn error—
Window residual—
Numbers appear once a path is loaded.
Take it back
Coordinates are exact and evenly spaced. The SVG path is a fit — tangents stay continuous, curvature breaks stay small.