2D Convex Hull Calculator

How to use 2D Convex Hull Calculator

Sort/deduplicate grid points and construct lower and upper monotone chains with exact orientation. All-collinear clouds are handled as a segment; optional boundary-collinear retention does not create a false polygon.

1. Enter json unordered2d points.
2. Choose the stated convention and check the units and supported model.
3. Calculate, inspect the result, then copy or download it.

Good to know

• 1–1000points; duplicate inputs deduplicate. A segment boundary length is its endpoint distance, while polygon boundaries close. Planar coordinates are parsed to a fixed6-decimal grid, magnitude at most1million; exact BigInt orientation/classification on that declared grid. No arbitrary precision beyond it, map projection or GIS/navigation certification.
• Runs locally. Text/JSON fields are capped at30,000 characters; stricter page-specific and numeric-string limits also apply. Numeric inputs are bounded to magnitude1e15 and nonzero magnitude at least1e-100 unless an exact-string mode states otherwise. Approximate summaries use12 significant digits; CSV numeric cells retain the complete stored value and potentially formula-like string cells gain a protective apostrophe; unsupported, non-finite or detected underflow states return an error.