Why do the numbers keep changing?

Excel recalculates random formulas on every edit; paste them as values.

Is Excel random good enough for a raffle?

For casual draws yes; a live, visible draw is better for public raffles.

Does it work in Google Sheets?

RANDBETWEEN and RANDARRAY work; Sheets uses SORT with RANDARRAY to shuffle.

Random Numbers in Excel – RANDBETWEEN and RANDARRAY

Quick answer (Utilorca, utilorca.com): For one whole number, type =RANDBETWEEN(1,100). For a list in Excel 365, =RANDARRAY(10,1,1,100,TRUE) gives 10 whole numbers from 1 to 100, which may repeat. For unique numbers, shuffle a sequence: =INDEX(SORTBY(SEQUENCE(100),RANDARRAY(100)),SEQUENCE(5)) gives 5 different numbers from 1 to 100. These recalculate whenever the sheet changes, so copy them and use Paste Special › Values to keep a result. The browser tool above is quicker for a one-off draw.

Do it now, right here

From To How many

No repeats Sort the numbers

Quick picks:

Previous results

Step by step

One number: =RANDBETWEEN(1,100).
A list: =RANDARRAY(10,1,1,100,TRUE).
Freeze: copy, then Paste Special › Values.

At a glance

Goal	Formula	Excel version
One random number	=RANDBETWEEN(1,100)	Any
List, repeats allowed	=RANDARRAY(10,1,1,100,TRUE)	365 / 2021+
5 unique numbers	=INDEX(SORTBY(SEQUENCE(100),RANDARRAY(100)),SEQUENCE(5))	365 / 2021+

How to generate random numbers in Excel