What is the syntax for IMSEC in Excel?

The syntax for IMSEC is: =IMSEC(inumber)

What are common errors with IMSEC?

#VALUE! if not a valid complex number

How do I use the IMSEC function?

To use IMSEC, type =IMSEC( in a cell and provide the required arguments. Excel will show you the syntax and parameter hints as you type. Make sure to close the parentheses and press Enter to execute the function.

Why is IMSEC not working in my Excel?

Common issues with IMSEC include #VALUE! if not a valid complex number. Start by checking the syntax =IMSEC(inumber), then verify each referenced cell or range.

Engineering

IMSEC Function in Excel

Returns the secant of a complex number.

Syntax

=IMSEC(inumber)

Arguments

inumber (required): A complex number in x+yi or x+yj format

Examples

=IMSEC("1+2i") - Secant of 1+2i - Result: 0.151+0.231i

IMSEC in technical sheets

Document units in adjacent cells — many engineering functions require exact unit strings.
Use [CONVERT](/functions/convert/) for unit changes before specialized formulas.
Validate inputs with [ISNUMBER](/functions/isnumber/) and range checks.

Common errors

#VALUE! if not a valid complex number

Use cases

Complex number calculations
Engineering

Frequently asked questions

What is the IMSEC function in Excel? IMSEC returns the secant of a complex number. The syntax is =IMSEC(inumber). Typical use cases include complex number calculations, engineering.
How do I use the IMSEC function? To use IMSEC, type =IMSEC( in a cell and provide the required arguments. Excel will show you the syntax and parameter hints as you type. Make sure to close the parentheses and press Enter to execute the function.
Why is IMSEC not working in my Excel? Common issues with IMSEC include #VALUE! if not a valid complex number. Start by checking the syntax =IMSEC(inumber), then verify each referenced cell or range.

Editorial review

Reviewed by Excel.Directory Editorial Team. Updated May 2026.