Choose which items to test. Enter the population size, the sample size and a seed. The tool picks item numbers at random or at a fixed interval, and the same seed gives the same selection again, so you can show how it was done.
Get the sample size from your sampling plan or the audit sampling calculator. Random selection gives every item the same chance. Systematic selection takes every k-th item from a random start, so avoid it where the list follows a pattern.
Selection runs in your browser and is repeatable for the same inputs. Keep the method, population, sample size, first item number and seed in the working paper. If a selected item cannot be tested, document why and how you replaced it.
A reviewer should be able to see how items were chosen and, ideally, repeat the selection. A seeded generator makes that possible: the same seed, population and sample size give the same list. Write the seed in the working paper. Choose random selection when the order of the list carries no pattern, and systematic selection when you want even coverage across a long list, such as a full year of vouchers.
Random selection draws unique item positions using a seeded generator, then adds your first item number so the result matches your own numbering. Systematic selection divides the population by the sample size to get an interval, picks a random start inside the first interval and takes every interval after that.
Because the generator is seeded, the same inputs always give the same items. Change the seed to get a different selection.
The tool picks positions only. It does not check that the population is complete, which you must do separately.
A population of 2,400 vouchers and a sample of 60, selected systematically.
