Line and Segment Intersection Calculator

How to use Line and Segment Intersection Calculator

Exact BigInt cross products distinguish parallel/collinear and crossing configurations. Infinite-line mode rejects zero-length definitions; segment mode handles point segments. A unique intersection has exact rational coordinates plus decimal output.

1. Enter json first endpoint pair, json second endpoint pair.
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

• Two endpoint pairs. Segment endpoints are included; infinite coincident lines do not produce an invented point. 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.