Index / Developer

SVG Path Optimizer

Shortens the d attribute of a path, then samples both the original and the result and reports how far apart they ever get. An optimizer you cannot check is worse than none.

Path data

Paste the contents of a d attribute. The surrounding <path> tag is not needed, and is ignored if you paste it anyway.

Optimizations

Decimal places 3 This is an absolute tolerance, not a relative one. Three places is generous inside a 24-unit viewBox and coarse inside a 1-unit one. The deviation figure tells you which you have.

Relative commands where shorter Collapse axis-aligned lines to h and v Drop zero-length line segments Omit repeated command letters

Waiting for a path

Saved --

Max deviation --

Result

--

Both paths, drawn on top of each other

grey solid: before · orange dashed: after

What changed

How the check works, and what it can and cannot tell you The result is parsed again from the text you see, not carried over from the optimizer's own state. Both paths are then flattened into several hundred points each, and the figure above is the Hausdorff distance between the two sets: the furthest any point on either curve is from the nearest point on the other. It is in user units, the same units as the path. Rounding to n places can move a point by up to half of 10⁻ⁿ in each axis, so a healthy deviation sits at or just under that.

It compares outlines, not fills. A change to the winding direction of a subpath would not show up here and would change how fill-rule: evenodd renders. Nothing this tool does reorders or reverses a subpath, but that is the one thing the check does not independently confirm.

Arc flags are written out separated, never packed. Packing them (a1 1 0 011 1) is legal, and this tool reads it, but enough parsers get it wrong that the two bytes are not worth it.

A zero-length line is kept when the next command is S or T. Those take their first control point by reflecting the previous curve's, and only when the previous command was itself a curve — so removing the line between them silently changes the shape.

Command choice is greedy, one segment at a time. Occasionally a longer choice early would let more letters be omitted later; this does not look for that, so the output is short but not provably shortest.