How to Generate Random Numbers in Excel

Excel has built-in functions for generating random numbers. This guide covers the three you'll use most, with examples. Prefer a one-click tool? Try our free Random Number Generator.

RAND: a random decimal between 0 and 1

The RAND() function returns a random decimal greater than or equal to 0 and less than 1.

=RAND()

To get a random decimal between two values a and b, use:

=RAND()*(b-a)+a

RANDBETWEEN: a random whole number in a range

The most popular option. RANDBETWEEN(bottom, top) returns a random integer between the two values, inclusive.

=RANDBETWEEN(1, 100)

This gives a whole number from 1 to 100. Drag the formula down a column to generate a whole list at once.

RANDARRAY: many random numbers at once

In Microsoft 365 and Excel 2021, RANDARRAY() fills a range with random numbers in a single formula.

=RANDARRAY(5, 1, 1, 100, TRUE)

This produces 5 rows, 1 column, whole numbers from 1 to 100. Set the last argument to FALSE for decimals.

Common tasks

Random numbers with no repeats

Excel's random functions can repeat values. To get unique numbers, generate a column of RANDBETWEEN values, then remove duplicates, or use =SORTBY(SEQUENCE(100), RANDARRAY(100)) and take the first N. Our generator has a built-in "No repeats" toggle that does this for you.

Stop numbers from changing

Excel's random functions recalculate every time the sheet changes. To freeze a result, copy the cells and use Paste Special → Values.

Excel vs an online generator

Excel is great when your data already lives in a spreadsheet. For a quick, shareable result, no-repeats draws, or generating names, words and passwords, an online tool is faster. Explore the full set of Toolssy generators.