engineering

Bilinear Interpolation Calculator

Two-variable interpolation at a point (x,y) from four corner values — used for steam tables and two-variable data

Bilinear Interpolation Calculator

Two-variable interpolation from four corner values — used for steam tables, heat transfer data, and other two-parameter lookups.

f(x,y) = Q₁₁(1-t)(1-u) + Q₂₁·t(1-u) + Q₁₂(1-t)·u + Q₂₂·t·u
t = (x−x₁)/(x₂−x₁), u = (y−y₁)/(y₂−y₁)

Grid Coordinates

Corner Values

Q(x₁, y₂) — top-left
Q(x₂, y₂) — top-right
Q(x₁, y₁) — bottom-left
Q(x₂, y₁) — bottom-right

Query Point

Result

f(150, 1.5)
3.50000
t (fraction in x)
0.500000
u (fraction in y)
0.500000

How to Use This Calculator

1

Enter your input values

Fill in all required input fields for the Bilinear Interpolation Calculator. Most fields include unit selectors so you can work in your preferred unit system.

2

Review your inputs

Double-check that all values are correct and that you have selected the right units for each field. Incorrect units are the most common source of calculation errors.

3

Read the results

The Bilinear Interpolation Calculator instantly computes the output and displays results with units. All calculations happen in your browser — no loading time and no data sent to a server.

Formula Reference

Bilinear Interpolation Calculator Formula

See calculator inputs for the governing equation

Variables: All variables and their units are labeled in the calculator interface above.

When to Use This Calculator

  • Use the Bilinear Interpolation Calculator when solving homework or exam problems that require quick numerical verification of your hand calculations.
  • Use it during the design phase to rapidly iterate on parameters before running detailed finite element simulations.
  • Use it when reviewing a colleague's calculation or checking a vendor's data sheet for plausibility.
  • Use it to generate reference data for a technical report or presentation without manual computation.

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