Skip to content
ENExplore Calculators

Winner Selector Calculator

Work out winner selector instantly with clear inputs, formula shown and shareable results.

About Winner Selector Calculator

Winners are drawn without replacement, so the chance of missing every prize is C(total - your entries, winners) / C(total, winners) and the answer is one minus that. Multiple prizes raise your odds more than a single-draw calculation suggests, because each unsuccessful draw removes a rival entry from the pool.

Formulas

Chance of no win

P(none) = C(total - yours, winners) / C(total, winners)

Chance of winning

P(win) = 1 - P(none)

Worked example

With the default values below, Winner Selector Calculator returns Chance of winning something of 5.9040%. Change any input above and every figure here is recalculated in your browser.

Inputs used

Total entriesminimum 1
250
Your entriesminimum 1
5
Number of winnersminimum 1
3

Results

Chance of winning something
5.9040%
Odds are one in
16.94
Prizes expected
0.0600
Chance in a single draw
2.0000%

Step by step

  1. 1Values used
  2. 2Chance of no win
  3. 3Chance of winning
  4. 4Chance of winning something= 5.9040
  5. 5Odds are one in= 16.94
  6. 6Prizes expected= 0.0600
  7. 7Chance in a single draw= 2.0000

Assumptions and limits

  • The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
  • In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
  • Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Frequently Asked Questions

How is the Winner Selector figure worked out?

P(none) = C(total - yours, winners) / C(total, winners). Winners are drawn without replacement, so the chance of missing every prize is C(total - your entries, winners) / C(total, winners) and the answer is one minus that.

Why does this matter?

Multiple prizes raise your odds more than a single-draw calculation suggests, because each unsuccessful draw removes a rival entry from the pool.

What do I need to enter?

Enter total entries, your entries, number of winners. The defaults shown are a realistic worked example — swap in your own figures to get a result you can use.

Related Calculators

Winner Selector Calculator | Calcrivo