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In this guide, we’re going to show you how to calculate area under curve in Excel.

Unfortunately, there isn't a single function or feature that can calculate area under curve in Excel. You can still rely on integrals to calculate area. On the other hand, Excel can help us with a simpler approach as well.

## Calculating area under curve by trapezoidal rule

The trapezoidal rule is a technique for approximating the region under the graph as a trapezoid and calculating its area. The rule can be depicted as following:

Because we have the data which generates the chart, we can easily transform the above formula into a format that Excel can calculate each trapezoid's area individually.

1. Start by inserting a helper column in your data set. Adjacent columns will ease copying of the formula. This column will calculate the area of each trapezoid between data points (x).
2. Enter the area formula starting from the second row. The formula will refer the data points in the same (k) and the previous row (k-1).
=(C6+C5)/2*(B6-B5)
3. Sum all area values to find the total area under the curve.

## Using Chart Trendline

An alternative approach is to use the equation of the plotted curve. Excel can plot a trendline based on your values and generate an equation for the trendline as well.