Angle Converter

Trying to program a CNC machine or pass a high school trigonometry exam? Use our free angle converter to translate geometric arc measurements instantly. While everyday society uses the 360-degree circle, advanced mathematics and physics rely entirely on Pi-based radians. This tool flawlessly converts standard degrees into radians, gradians, and arcminutes without forcing you to memorize complex Pi formulas.

[AdSense Unit 1 Placeholder]

How to Use This Geometry Translation Tool

Translating angle trajectories requires no mental math. Select the measurement you currently have from the top dropdown (for example, Degrees) and enter your number. Next, select your target unit in the bottom dropdown (for example, Radians).

The converter utilizes JavaScript to instantly update the output as you type. It relies on the absolute precision of the Math.PI object built into modern web browsers, guaranteeing flawless accuracy for surveyors, machinists, and engineers.

Degrees vs Radians Explained

Why do we use two completely different systems to measure a circle? The Degree system was invented by the ancient Babylonians. Because their civilization used a Base-60 counting system (instead of our modern Base-10), they decided to divide a circle into 360 equal slices. This arbitrary number stuck around for thousands of years and is still used by compasses today.

In modern calculus and physics, the arbitrary 360-degree scale breaks mathematical formulas. Scientists needed a measurement based purely on the physical geometry of the circle itself. They created the Radian. There are exactly 2π (roughly 6.28) radians in a full circle. By tying the angle directly to the radius and Pi, massive calculus equations suddenly become elegantly simple.

Angle Converter Examples

If you are writing code for a 3D video game engine, the computer's internal trigonometry functions (like Math.sin()) will strictly require input in radians. If a character needs to turn exactly 90 degrees to face a wall, you cannot type "90" into the code. Using our angle converter, you discover 90 degrees equals exactly 1.570796 radians. You type 1.57 into the codebase, and the character turns perfectly.

If you are a long-range marksman, you will constantly hear the term "MOA" (Minute of Arc). A Minute of Arc is exactly 1/60th of a single degree. Because it is so tiny, it perfectly translates to exactly 1 inch of deviation for every 100 yards a bullet travels. If your rifle scope is off by 2 MOA at 300 yards, your bullet will hit exactly 6 inches away from the bullseye.

[AdSense Unit 2 Placeholder]

Tips for Trigonometry Math in 2026

  • Memorize the 180 Rule: The most important anchor point in trigonometry is a straight line. 180 degrees is exactly equal to 1 Pi radian (3.14159...). If 180 degrees equals Pi, then a 90-degree right angle is exactly half-Pi (π/2), and a full 360-degree circle is Two-Pi (2π).
  • Use the correct calculator mode: Every year, thousands of college freshmen fail their physics exams because their graphing calculator is set to "Degree mode" while the test questions are written in "Radian mode." Always check your TI-84 settings before a test.
  • What is a Gradian? A Gradian (or Gon) was an attempt by the French metric system to replace the 360-degree circle with a Base-10 metric circle. In this system, a right angle is exactly 100 gradians, and a full circle is 400 gradians. It failed to catch on globally, but is still used by some civil engineers in Europe.

Frequently Asked Questions

How many degrees are in a circle?

A full geometric circle contains exactly 360 degrees. Therefore, a straight line is 180 degrees, and a perfect right angle is 90 degrees.

What is a radian?

A radian is the standard unit of angular measure used in mathematics. One radian is the angle subtended at the center of a circle by an arc that is equal in length to the radius of the circle.

How do you convert degrees to radians?

To convert degrees to radians, multiply the number of degrees by Pi and then divide by 180. The formula is: Radian = Degree x (π / 180).

What is a Minute of Arc (MOA)?

An arcminute is exactly 1/60th of a single degree. It is heavily used in astronomy to measure stars, and in marksmanship to dial in the accuracy of long-range rifle scopes.

Stop doing advanced Pi mathematics in your head. Scroll back up and convert your geometric angles instantly.