home page

Cubic Bezier Curve Calculator

Given a cubic Bezier curve with control points P1, P2, P3, and P4, and for 0 ≤ t ≤ 1, you can calculate the control points Q1, Q2, Q3, and Q4 for a particular piece of the same Bezier curve over an interval [t0,t1] ⊆ [0,1]. The +/- buttons will increase/decrease the t value by 0.005.

P1  x:
 y:
P2  x:
 y:
P3  x:
 y:
P4  x:
 y:

Q1  x:
 
 y:
 

Q2  x:
 
 y:
 

Q3  x:
 
 y:
 

Q4  x:
 
 y:
 
   t0:  t1:
  


Convert Quadratic to Cubic

Given a quadratic Bezier curve with control points P1, P2, P3, you can calculate the control points Q1, Q2, Q3, and Q4 for the same Bezier curve in cubic form. Note that Q1 = P1 and Q4 = P3.
P1  x:
 y:
P2  x:
 y:
P3  x:
 y:
Q1  x:
 
 y:
 

Q2  x:
 
 y:
 

Q3  x:
 
 y:
 

Q4  x:
 
 y: