The interpolation calculator allows you to calculate the value of a point along a line if you know two other points on that line. Enter the first point (First X, First Y) and the second point (Second X, Second Y) to establish the general direction of the line. Then, enter the X value of the third point.
This calculator applies the linear interpolation formula to derive the dependent (y) value of the third point. This presumes the three points are in a straight line and that there is no natural variation or error in measurement. Linear interpolation works fairly well for simple models, especially when you are trying to estimate data relatively close to your trusted measurements.