Bilinear Interpolation Calculator

Enter x₀.
Enter x₁.
Enter y₀.
Enter y₁.
Enter f(x₀,y₀).
Enter f(x₁,y₀).
Enter f(x₀,y₁).
Enter f(x₁,y₁).
Enter target x.
Enter target y.
Math

Bilinear Interpolation: calculate results from explicit inputs, with a formula and worked example.

Formula

u=(x−x₀)/(x₁−x₀); v=(y−y₀)/(y₁−y₀); f=(1−u)(1−v)f₀₀+u(1−v)f₁₀+(1−u)vf₀₁+uvf₁₁

Example Calculation

Example inputs
  • x₀: 0
  • x₁: 2
  • y₀: 0
  • y₁: 2
  • f(x₀,y₀): 0
  • f(x₁,y₀): 2
  • f(x₀,y₁): 2
  • f(x₁,y₁): 4
  • Target x: 1
  • Target y: 1

For corner values 0,2,2,4 on [0,2]×[0,2], the center value is 2.

Frequently asked questions

How do I use this calculator?

Enter x₀, x₁, y₀, y₁, f(x₀,y₀), f(x₁,y₀), f(x₀,y₁), f(x₁,y₁), target x, target y. The result updates automatically. Use Reset to restore the example values.

What method does it use?

u=(x−x₀)/(x₁−x₀); v=(y−y₀)/(y₁−y₀); f=(1−u)(1−v)f₀₀+u(1−v)f₁₀+(1−u)vf₀₁+uvf₁₁. Real finite inputs. Numeric results use floating-point arithmetic; this is not a symbolic computer algebra system. Interpolation only, without extrapolation.

Why might a rounded result differ?

The calculation keeps full numeric precision internally, then rounds the displayed result. Rounding intermediate steps by hand can produce a slightly different answer.

Are my inputs saved online?

No. This calculator processes your inputs in your browser. A recently used list stores only calculator names on this device, not your entered values.

Check the assumptions and units before using this result. Read about calculation methods.