Log Function

Applies To
Access for Microsoft 365 Access 2024 Access 2021 Access 2019 Access 2016

Returns a Double specifying the natural logarithm of a number.

Syntax

Log(number⁠)⁠

The required number⁠argument is a Double or any valid numeric expression greater than zero.

Remarks

The natural logarithm is the logarithm to the base e. The constant e is approximately 2.718282.

You can calculate base-n logarithms for any number x by dividing the natural logarithm of x by the natural logarithm of n as follows:

Logn(x) = Log(x) / Log(n)

The following example illustrates a custom Function that calculates base-10 logarithms:

Note

Examples that follow demonstrate the use of this function in a Visual Basic for Applications (VBA) module. For more information about working with VBA, select Developer Reference in the drop-down list next to Search and enter one or more terms in the search box.

Static Function Log10(X)
    Log10 = Log(X) / Log(10#)
End Function

Query example

Expression Results
SELECT Log(90) AS Logarithm FROM ProductSales GROUP BY Log(90); Returns the "Log" of the number argument and displays in the column Logarithm.

VBA example

This example uses the Log function to return the natural logarithm of a number.

Dim MyAngle, MyLog
' Define angle in radians.
MyAngle = 1.3
' Calculate inverse hyperbolic sine.
MyLog = Log(MyAngle + Sqr(MyAngle * MyAngle + 1))