Rotation Calculator

Rotate a point about the origin by a given angle.

x′ 0
y′ 1

Formula: x′ = x·cosθ − y·sinθ ; y′ = x·sinθ + y·cosθ

Step-by-step with your numbers:
1. Values used:
2. x = 1
3. y = 0
4. Angle (counter-clockwise) = 90 °
5.
6. x′ = x x y = 1 x 0 = 0
7. y′ = x + y = 1 + 0 = 1
Did we solve your problem today?

Rotate any point counter-clockwise around the origin by a chosen angle.

The math behind it

Apply the 2D rotation matrix: x′ = x cosθ − y sinθ and y′ = x sinθ + y cosθ.

Worked example

Rotating (1, 0) by 90° gives (0, 1).

FAQ

How do I rotate about another point?

Translate so that point is the origin, rotate, then translate back.