Turn calculator
How many turns does each person get?
Before you ask people to sign on for a season, it helps to know what you’re asking. Put in the names and the dates, and the Turns each list under the roster shows exactly how many each person gets.
Your roster appears here
Type the names, choose the first date and how it repeats, then press Count the turns. Each date goes to whoever has had the fewest turns so far, so the turns are shared out and nobody is skipped.
The sum
Turns each is three numbers: how many dates, how many places on each date, and how many people.
Dates × places on each date ÷ people = turns each. If it doesn’t divide, the remainder is how many people get one extra turn.
Take a club canteen open every Saturday of the year with two people on. That’s 52 Saturdays × 2 places = 104 places. Nine people share them: 104 ÷ 9 = 11, with 5 left over. So five people do 12 Saturdays and four people do 11. There is no way to split 104 into nine whole numbers that are all the same, and it helps to say so up front.
Type nine names into the tool above, set it to every week on Saturday, 52 dates, 2 people on each date, and the Turns each list shows those numbers: five 12s and four 11s.
Worked examples
| Roster | Dates | Places each | People | Total places | Turns each |
|---|---|---|---|---|---|
| Canteen, every Saturday for a year | 52 | 2 | 9 | 104 | 5 people 12, 4 people 11 |
| Bins, every week for a year | 52 | 1 | 4 | 52 | 13 each |
| Readers, every second Sunday for a year | 26 | 3 | 10 | 78 | 8 people 8, 2 people 7 |
| School pick-up, weekdays for a 10-week term | 50 | 1 | 6 | 50 | 2 people 9, 4 people 8 |
| Committee supper, monthly for a year | 12 | 4 | 15 | 48 | 3 people 4, 12 people 3 |
What the number tells you
- Is it too much? Twelve Saturdays a year is one a month. Most volunteers can say yes to that. Twenty-six is every second week, and you’ll start to lose people.
- How many more people do you need? Decide the turns you’re comfortable asking for, then divide the total places by it. 104 places at about 8 turns each needs 13 people.
- Who gets the extra one? Say it out loud: “five of us will do one more this year.” In a live roster the extras go to whoever has had fewer turns, so they come round.
- Holidays move it. If people mark weeks they’re away, those turns go to others, so the final count shifts a little. That’s normal.
The guide on how often to roster volunteers goes further into what people will happily take on.
Keeping count during the year
The count you make in January is a plan. By June, two people have left, one has joined and someone was away for a month. In FairTurns the Turns booked chart beside Fill shows how many dates each person has right now, and Fill gives each empty place to whoever has had the fewest turns, so the count keeps itself. When someone leaves, Redistribute shares their dates out and shows the new count before you confirm. It’s free for any number of people. See fair fill for how it works.
Questions
How do I work out how many turns each person gets?
Multiply the number of dates by the number of places on each date, then divide by the number of people. Any remainder is how many people get one extra turn.
Why do some people get one more turn than others?
Because the places don’t always divide by the number of people. 104 places for nine people is 11 each with 5 over, so five people do 12.
Can I give an experienced person more turns on purpose?
Yes, in FairTurns Pro. Set each person to More often, Normal, Less often or Now and then, position by position. This calculator treats everyone alike.
What is the most this tool can count?
Up to 104 dates, 60 names and 10 people on each date, so two years of weekly dates or a year of two-a-week.
Read next
Fair rotation generator
A rotating schedule from a list of names, with the rule it follows spelled out.
How often should volunteers be rostered?
Do the sum, watch for burnout, and set a gap between turns that keeps people coming back.
Club canteen and kiosk
Every family takes a canteen shift, the season is mapped out, and one link shows who’s on.
Make your roster free
Click a day, add people, share one link. No card, no limit on people or dates.