1. What is an Angle Between 2 Points Calculator?

Definition: This calculator computes the angle in degrees between two points in a 2D plane, measured from the positive x-axis.

Purpose: It's useful in geometry, computer graphics, navigation, and engineering applications where directional relationships between points are needed.

2. How Does the Calculator Work?

The calculator uses the arctangent2 (atan2) function:

Where:

• \( θ \) — Angle in degrees (0° to 360°)
• \( (x_1, y_1) \) — Coordinates of first point
• \( (x_2, y_2) \) — Coordinates of second point

Explanation: The atan2 function calculates the angle between the positive x-axis and the line connecting the two points, properly handling all quadrants.

3. Understanding the Results

Details: The angle is measured counter-clockwise from the positive x-axis:

• 0° - Points to the right (positive x-direction)
• 90° - Points upward (positive y-direction)
• 180° - Points to the left
• 270° - Points downward

4. Using the Calculator

Tips: Enter the coordinates of both points. The calculator will determine the angle from point 1 to point 2.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between atan and atan2?
A: atan2 considers the signs of both coordinates to determine the correct quadrant, while atan doesn't.

Q2: What coordinate system is used?
A: Standard Cartesian coordinate system with x increasing to the right and y increasing upward.

Q3: Can I use this for geographic coordinates?
A: Not directly - geographic coordinates require spherical trigonometry calculations.

Q4: How is the angle range determined?
A: The result ranges from -180° to +180°, but is typically normalized to 0°-360°.

Q5: What if both points are the same?
A: The angle is undefined (division by zero) as there's no direction between identical points.