What is the syntax for IMLOG10 in Excel?

The syntax for IMLOG10 is: =IMLOG10(inumber)

What are common errors with IMLOG10?

#NUM! if not valid complex number

How do I use the IMLOG10 function?

To use IMLOG10, type =IMLOG10( 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 IMLOG10 not working in my Excel?

Common issues with IMLOG10 include #NUM! if not valid complex number. Start by checking the syntax =IMLOG10(inumber), then verify each referenced cell or range.

Engineering

IMLOG10 Function in Excel

Returns the base-10 logarithm of a complex number.

Syntax

=IMLOG10(inumber)

Arguments

inumber (required): Complex number

Examples

=IMLOG10("1+i") - Log base 10 of complex - Result: 0.151+0.341i

IMLOG10 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

#NUM! if not valid complex number

Use cases

Complex analysis
Engineering
Signal processing

Frequently asked questions

What is the IMLOG10 function in Excel? IMLOG10 returns the base-10 logarithm of a complex number. The syntax is =IMLOG10(inumber). Typical use cases include complex analysis, engineering, signal processing.
How do I use the IMLOG10 function? To use IMLOG10, type =IMLOG10( 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 IMLOG10 not working in my Excel? Common issues with IMLOG10 include #NUM! if not valid complex number. Start by checking the syntax =IMLOG10(inumber), then verify each referenced cell or range.

Editorial review

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