Rnd Function

This page is specific to the Visual Basic for Applications (VBA) Language Reference for Office 2010.

Returns a Single containing a random number.

Syntax

Rnd[(number)]

The optional number argument is a Single or any valid numeric expression.

Return Values

If number is	Rnd generates
Less than zero	The same number every time, using number as the seed.
Greater than zero	The next random number in the sequence.
Equal to zero	The most recently generated number.
Not supplied	The next random number in the sequence.

Remarks

The Rnd function returns a value less than 1 but greater than or equal to zero.

The value of number determines how Rnd generates a random number:

For any given initial seed, the same number sequence is generated because each successive call to the Rnd function uses the previous number as a seed for the next number in the sequence.

Before calling Rnd, use the Randomize statement without an argument to initialize the random-number generator with a seed based on the system timer.

To produce random integers in a given range, use this formula:

Int((upperbound - lowerbound + 1) * Rnd + lowerbound)

Here, upperbound is the highest number in the range, and lowerbound is the lowest number in the range.

Note

To repeat sequences of random numbers, call Rnd with a negative argument immediately before using Randomize with a numeric argument. Using Randomize with the same value for number does not repeat the previous sequence.

Example

This example uses the Rnd function to generate a random integer value from 1 to 6.

Dim MyValue
MyValue = Int((6 * Rnd) + 1)    ' Generate random value between 1 and 6.