Interpolation Calculator



In the world of data analysis, there are often situations where we have data points scattered along a continuum, and we need to estimate values at points that lie between the known data points. This is where interpolation comes into play, and an Interpolation Calculator can be your trusty tool in making these estimations. In this article, we will explore what interpolation is, the formula behind it, how to use an Interpolation Calculator, provide a practical example, and answer some frequently asked questions about this valuable tool.


Interpolation is a mathematical technique used to estimate values between two known data points. The most common method for linear interpolation, suitable for data that appears to follow a linear trend, uses the following formula:

y = y1 + ((x – x1) / (x2 – x1)) * (y2 – y1)


  • y is the estimated value between y1 and y2 at the point x.
  • x is the point at which you want to estimate a value.
  • x1 and x2 are the known data points nearest to x.
  • y1 and y2 are the corresponding values of x1 and x2.

How to Use an Interpolation Calculator

Using an Interpolation Calculator is straightforward. Here are the steps to follow:

  1. Gather your data: Ensure you have a set of data points with known x and y values. You’ll need at least two data points to perform interpolation.
  2. Determine the point you want to estimate (x): Identify the specific value of x for which you want to estimate a corresponding y value.
  3. Input your data: Enter your known data points into the Interpolation Calculator. Typically, this involves providing the x and y values for two points, i.e., (x1, y1) and (x2, y2).
  4. Perform the calculation: Hit the calculate button, and the calculator will use the interpolation formula to estimate the y value at the specified x.
  5. Review the result: The Interpolation Calculator will display the estimated y value. This value represents the best estimate of the data point at x based on the linear trend between the two known data points.


Let’s say you have temperature data for a specific location over two days:

  • Day 1: x1 = 24°C and y1 = 75°F
  • Day 2: x2 = 32°C and y2 = 89°F

You want to estimate the temperature in Fahrenheit when it’s 28°C. Using the Interpolation Calculator:

x = 28°C x1 = 24°C x2 = 32°C y1 = 75°F y2 = 89°F y = 75 + ((28 – 24) / (32 – 24)) * (89 – 75) = 75 + (4/8) * 14 = 75 + 7 = 82°F

So, at 28°C, the estimated temperature in Fahrenheit is 82°F.


Q1: Can interpolation be used for non-linear data? A1: Interpolation is best suited for linear trends. For non-linear data, other techniques like polynomial interpolation or spline interpolation may be more appropriate.

Q2: Are there any limitations to interpolation? A2: Interpolation assumes a continuous and smooth transition between data points. It may not provide accurate results if the data has abrupt changes or outliers.

Q3: Is interpolation the same as extrapolation? A3: No, interpolation estimates values within the range of known data, while extrapolation estimates values outside that range. Extrapolation can be less reliable, especially when data trends change dramatically.


Interpolation calculators are indispensable tools for data analysts, engineers, and scientists. They provide a quick and accurate way to estimate values between known data points, helping us make informed decisions when dealing with incomplete or scattered data. By understanding the formula and following a few simple steps, you can harness the power of interpolation to bridge the gaps in your data analysis, making it a valuable addition to your analytical toolkit.

Leave a Comment