How this calculation works
Rotate a planar point about a chosen centre.
THE FORMULA
Translate to the pivot, multiply by the rotation matrix, then translate backA worked example
Rotating (3,2) by 90° around (1,2) gives (1,4).
Good to know
Positive angles rotate counterclockwise.
Reference: OpenStax Algebra and Trigonometry, Trigonometric Applications (opens in a new tab) ↗
Read the result
Rotate a planar point about a chosen centre.
The primary result is labeled “Rotated x”. Keep the input definitions in view when comparing this result with another method.
Try a related calculation
Positive angles rotate counterclockwise.
For a related exercise, try the circle calculator.
A few questions, answered
How can I check the default inputs by hand?
Rotating (3,2) by 90° around (1,2) gives (1,4).
Which rule does this calculator apply?
Translate to the pivot, multiply by the rotation matrix, then translate back