Angle Between Lines Calculator

About This Tool

This calculator provides an efficient way to find the angle between two lines, either based on their slopes or direction vectors. It is ideal for engineers, students, and educators needing precise geometric calculations.
The tool accepts slope inputs (e.g., 3, -1.2) or vector components (x1, y1, x2, y2). Users can choose units in degrees or radians for results, making it versatile for various applications.
After input, the calculator applies trigonometric formulas, such as arctangent of the difference of slopes divided by (1 + product of slopes), or vector dot product formulas for angles between vectors. Results are displayed instantly, with options to copy or export.
Additional features include input validation, error handling for invalid or missing inputs, and a clean, responsive interface suitable for mobile and desktop browsers. The tool is designed to facilitate education, technical analysis, and quick geometric assessments.

Sign in to see all your usage