🎯 Polar Coordinate Converter

Convert between Cartesian (x,y) and polar (r,θ) coordinates instantly. Perfect for navigation, physics, and engineering applications.

📊 22,000+ conversions performed 🔄 Updated: February 2026 ⭐ 4.9/5 Rating

Understanding Coordinate Systems

Coordinate systems are fundamental tools for describing positions and locations in mathematics, physics, and engineering. The two most common systems are Cartesian coordinates, which use perpendicular x and y axes, and polar coordinates, which use distance and angle from a fixed point. Each system has advantages in different situations and applications.

Cartesian coordinates (x, y) are intuitive for describing rectangular grids, computer graphics, and linear motion. Polar coordinates (r, θ) are natural for describing circular motion, rotational systems, and radial patterns. Converting between these systems is essential in many fields, from robotics and navigation to signal processing and quantum mechanics.

Our converter handles both directions of conversion and provides additional information like quadrant determination and verification calculations. Understanding these coordinate systems and their relationships is crucial for advanced mathematics and practical applications in science and engineering.

Convert Coordinates

Cartesian Coordinates

Coordinate Systems Explained

Cartesian Coordinates (x, y)

Description: Uses perpendicular axes to locate points

Origin: Point (0, 0) where axes intersect

Advantages:

  • Intuitive for rectangular grids
  • Simple arithmetic operations
  • Easy visualization on paper
  • Natural for computer graphics

Best for: Linear motion, rectangular areas, computer graphics

Polar Coordinates (r, θ)

Description: Uses distance and angle from origin

Origin: Central point (pole) with r = 0

Advantages:

  • Natural for circular motion
  • Simplifies rotational problems
  • Efficient for radial patterns
  • Useful in physics and engineering

Best for: Circular motion, navigation, radar systems

Conversion Formulas

Cartesian to Polar

r = √(x² + y²)
θ = atan2(y, x)

Note: atan2(y, x) correctly handles all quadrants, unlike atan(y/x)

Polar to Cartesian

x = r × cos(θ)
y = r × sin(θ)

Note: θ can be in degrees or radians (specify units)

Real-World Applications

🧭 Navigation & GPS

Ships and aircraft use polar coordinates for navigation, where position is described by distance and bearing from reference points. GPS systems convert between coordinate systems for mapping.

📡 Radar & Sonar

Radar and sonar systems naturally work in polar coordinates, measuring distance and angle to targets. Data is often converted to Cartesian for display on rectangular screens.

🤖 Robotics

Robot arms use polar coordinates for rotational joints, while the workspace is often described in Cartesian coordinates. Conversion between systems is essential for motion planning.

🌌 Astronomy

Celestial coordinates use spherical systems (extension of polar), while telescope mounts convert to Cartesian for tracking. Star charts often use both systems.

📊 Data Visualization

Polar plots are ideal for cyclical data (time series, directional data), while Cartesian plots work better for linear relationships. Converting between formats aids analysis.

⚡ Engineering

Electrical engineers use polar coordinates for AC circuit analysis (magnitude and phase), while mechanical engineers use both systems for stress analysis and design.

Frequently Asked Questions

Why use atan2(y,x) instead of atan(y/x)?

The atan2 function correctly determines the quadrant of the angle and handles the case where x = 0 (which would cause division by zero). The regular atan function only returns values between -90° and 90°, while atan2 returns values from -180° to 180°, giving the full range needed for polar coordinates.

How do I handle negative radius values?

By convention, radius should be non-negative. If you get a negative radius, you can make it positive by adding 180° (or π radians) to the angle. For example, (-3, 45°) is equivalent to (3, 225°). Our converter automatically handles this by using the atan2 function correctly.

Which coordinate system should I use for my application?

Use Cartesian coordinates for rectangular grids, linear motion, computer graphics, and when you need simple arithmetic operations. Use polar coordinates for circular motion, rotational systems, radar/navigation applications, and when angle and distance from a center point are more meaningful than x,y positions.