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How To Use TAN function in Excel Explained

What is TAN function in Excel?

The TAN function in Excel calculates the tangent of an angle in radians. It is used to find the slope or tilt of an object and for various mathematical and engineering applications.


The TAN function in Excel is used to calculate the tangent of a given angle. It takes a single argument, the angle in radians, and returns the tangent of that angle. The function is part of the Math & Trig group of functions.

The function can be used in a variety of calculations, such as finding the angle of a triangle or the length of a side. It can also be used to calculate angles in trigonometry or in graphics applications.

To use the function in Excel, enter the angle in radians in a cell and then use the formula =Tan(angle). The result will be the tangent of the angle.

For example, if you want to find the tangent of an angle of 30 degrees, the formula would be =Tan(30*PI()/180). The result is 0.57735026919.

The function can also convert an angle in degrees to radians by multiplying the angle in degrees by PI()/180. For example, if you want to convert 45 degrees to radians, the formula would be =Tan(45*PI()/180), which will return the result 0.78539816339. 



TAN Function MS Excel - Excel Formula Cheat Sheet

How to use TAN function in your workbook:

  1. Open your Microsoft Excel workbook.
  2. Enter the data in the appropriate cells, making sure to include the angle that you want to apply the tan formula to.
  3. Select the cell you would like the function to be applied.
  4. Click on the “Formulas” tab at the top of the screen. Select the “Math & Trig” option from the list of dropdown options. Select the “Tan” option from the list of functions.
  5. Enter the cell reference of the angle you would like to apply the tan formula to in the “Number” field.
  6. Click “OK” and the function will be applied to the angle in the specified cell.

Frequently Asked Questions

Does Excel TAN formula returns degrees or radians?

The TAN function returns the tangent of an angle in radians, not degrees. If you have an angle in degrees, you need to convert it to radians before using the TAN function.

How to convert degrees to radians?
To convert degrees to radians, you can use the RADIANS function in Excel, which takes an angle in degrees and returns its equivalent value in radians. Once you have converted the angle to radians, you can use the TAN function to calculate its tangent.
Can the TAN function return an error? If so, what does it mean?

Yes, the TAN function in Excel can return an error. The most common error that can occur with the TAN function is the “#NUM!” error, which means that the input angle is too large or too small, causing the function to exceed the maximum or minimum value that Excel can handle.

Another error is the “#VALUE!” error, which means that the input argument is not recognized as a numeric value. This error can occur if the input argument is a text string or contains a non-numeric character.

Can the TAN function be used in combination with other functions in Excel?

You can use the TAN function together with the SIN and COS functions to calculate the slope or gradient of a line, or with the ATAN function to convert the tangent of an angle back to its original angle in radians. The TAN function can also be used in more advanced functions, such as the LINEST function and the Fourier Analysis Toolpak, which are used for statistical and engineering analyses.

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