Quick Navigation
COT Function
Summary
The Excel COT function calculates the cotangent of an angle provided in radians. Cotangent is the reciprocal of tangent (1/tan(x)) and is essential for advanced trigonometric calculations in engineering, physics, and mathematical modeling.
Syntax
COT(number)Parameters
| Parameter | Type | Required | Description |
|---|---|---|---|
| number | Number |
Yes | The angle in radians. Absolute value must be less than 2^27. |
Using the COT Function
Use COT when you need cotangent values for trigonometric computations. Common in physics for pendulum calculations, electrical engineering for phase angles, and geometry for triangle analysis involving cotangents.
Common COT Examples
Basic Cotangent Calculation
=COT(30)Returns the cotangent of 30 radians (-0.156). Note: Use radians, not degrees.
Cell Reference Example
=COT(A1)Calculates cotangent of value in cell A1 (e.g., A1=45 returns 0.617).
Frequently Asked Questions
Common Errors and Solutions
#NUM!
Cause: Absolute value of number >= 2^27
Solution: Ensure |number| < 2^27 (134217728)
#VALUE!
Cause: Non-numeric input
Solution: Use only numbers or numeric formulas
#DIV/0!
Cause: number = 0
Solution: Cotangent(0) is undefined
Notes
- Input must be in radians, not degrees
- COT(x) = 1/TAN(x)
- Absolute value limit: |number| < 2^27
- Excel 2013+ only
Compatibility
Available in: Excel 2013, Excel 2016, Excel 2019, Excel 2021, Microsoft 365
Not available in: Excel 2010, Excel 2007, Excel 2003
Content last reviewed: December 11, 2025
Update frequency: As needed
Excel versions tested: Excel 2013+