Interpolation Calculator
Enter two known points (x₁, y₁) and (x₂, y₂), and the x-value you want to interpolate.
Result
Interpolated y:
How to Use the Interpolation Calculator
An Interpolation Calculator is a mathematical tool that estimates unknown values between two known data points using the method of linear interpolation.
This calculator is particularly useful in science, engineering, finance, and everyday problem-solving when you need to estimate missing values within a range.
What Is Interpolation?
Interpolation is the process of estimating an unknown value that lies between two known values. The most common type is linear interpolation, which assumes that the change between two points follows a straight line.
For example:
- If you know the temperature at 2 pm (20°C) and 4 pm (24°C), interpolation can estimate the temperature at 3 pm.
- If a stock price was $50 on Monday and $60 on Wednesday, interpolation helps predict its price on Tuesday.
How the Calculator Works
The formula for linear interpolation is:y=y1+(x−x1)(y2−y1)(x2−x1)y=y1+(x2−x1)(x−x1)(y2−y1)
Where:
- (x₁, y₁) = First known point
- (x₂, y₂) = Second known point
- x = The value you want to interpolate
- y = The estimated result
Steps to Use the Calculator
- Enter two known points: Fill in values for x₁, y₁, and x₂, y₂.
Example: (2, 4) and (6, 12). - Enter the x-value to interpolate: Type the x for which you want to find y.
Example: x = 4. - Click “Calculate Interpolated Value”: The calculator will display the estimated y-value.
Example result: y = 8.
Real-Life Applications of Interpolation
- Weather Forecasting: Estimating temperature, humidity, or rainfall between recorded times.
- Finance: Predicting stock values, interest rates, or economic indicators between two known dates.
- Engineering: Approximating material strength, thermal expansion, or pressure values.
- Science: Filling in missing experimental data points.
- Everyday Life: Estimating distances, fuel consumption, or calorie burn.
Interpolation Calculator FAQ
Q1: What is interpolation used for?
A: Interpolation is used to estimate unknown values between two known data points, providing a quick and practical approximation.
Q2: Can this calculator handle extrapolation?
A: This calculator is designed for interpolation (values within the known range). Extrapolation (values outside the range) can be done but may be less accurate.
Q3: Why can’t x₁ and x₂ be the same?
A: If x₁ = x₂, the formula breaks down (division by zero). You need two distinct x-values for interpolation.
Q4: Is interpolation always accurate?
A: Linear interpolation provides an estimate. It’s very accurate for values that change linearly, but less accurate for values that follow curves or irregular patterns.
Q5: What’s the difference between interpolation and regression?
A: Interpolation estimates missing values between known points, while regression creates a best-fit model for an entire dataset (often used for prediction and trend analysis).