📊 Linear Interpolation Calculator

Interpolate values between two points

Point 1 (x₁, y₁)

Point 2 (x₂, y₂)

x must be between x₁ and x₂

How to Use This Calculator

1

Enter Two Points

Input coordinates (x₁, y₁) and (x₂, y₂) of two known points.

2

Enter Interpolation Point

Input the x-coordinate where you want to interpolate (must be between x₁ and x₂).

3

Calculate

Press "Calculate Interpolation" to find the interpolated y-value.

Formula

y = y₁ + (y₂ - y₁)(x - x₁)/(x₂ - x₁)

where x₁ ≤ x ≤ x₂ for interpolation

Example: Points (1, 2) and (3, 6), interpolate at x = 2

y = 2 + (6 - 2)(2 - 1)/(3 - 1) = 2 + 4×1/2 = 4

About Linear Interpolation Calculator

The Linear Interpolation Calculator estimates values at points between two known points using linear interpolation. It assumes a straight line between the two points.

When to Use This Calculator

  • Data Analysis: Fill gaps in data between known points
  • Engineering: Estimate values from tables or charts
  • Mathematics: Interpolate function values
  • Science: Estimate measurements between data points

Frequently Asked Questions

What is linear interpolation?

Linear interpolation estimates values between two known points by assuming a straight line. Formula: y = y₁ + (y₂ - y₁)(x - x₁)/(x₂ - x₁).

What's the difference from extrapolation?

Interpolation estimates values between x₁ and x₂. Extrapolation estimates values outside this range (before x₁ or after x₂), which is less reliable.