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Linear Interpolation Calculator

Find a value between two known points using linear interpolation formula.

Last updated: 2/3/2026

Linear interpolation allows you to estimate a value within two known values in a sequence. It assumes a straight line relationship between the points.

Calculator Inputs

x₁ (First known x)*

y₁ (First known y)*

x₂ (Second known x)*

y₂ (Second known y)*

Target x (Calculate y)*

Results

Enter values above to see your results

How It Works

Enter two coordinate points (x₁, y₁) and (x₂, y₂). Enter a target x value to calculate its corresponding y value based on the slope between the points.

Worked Examples

Interpolate between (0, 0) and (10, 100) at x=5

Slope:(100 - 0) / (10 - 0)= 10

Apply Formula:0 + (5 - 0) * 10= 50

Tips & Best Practices

•If target x is outside the range of x₁ and x₂, this is technically "extrapolation" but the formula works the same.
•Useful for estimating data between rows in a table.