This trifecta calculator works out combinations and flexi percentages for exactas, trifectas and First Fours. A four-horse trifecta box is 4 × 3 × 2 = 24 combinations. Spend $12 on it and your flexi is 50%: if it lands, you collect half the declared dividend. On a $187.40 dividend, that’s $93.70.
The free calculator above handles straight, boxed, standout and by-position bets, so you can see the flexi before you choose how much to put on.
Trifecta calculator: combinations
| Bet | Horses | Combinations |
|---|---|---|
| Exacta box | 3 | 6 |
| Exacta box | 4 | 12 |
| Trifecta box | 4 | 24 |
| Trifecta box | 5 | 60 |
| Trifecta standout, 1 with 4 | 5 | 12 |
| First Four box | 5 | 120 |
Boxing every horse in any order gets expensive quickly: each extra horse in a trifecta box multiplies the combinations by more than the last one did. A standout, where one horse has to win and the others fill the places in any order, cuts the count to a fifth.
How flexi betting works
Dividends are declared for a $1 unit. Flexi lets you spend any amount instead, and your share is your outlay divided by the combinations:
Flexi % = outlay ÷ combinations × 100 Return = dividend × flexi % ÷ 100
A $10 exacta box on three horses is 6 combinations, so 166.7% flexi. You’d get 1.667 times the dividend. A $10 First Four box on 5 horses is 120 combinations and 8.3%. Low flexi isn’t wrong: it’s the cost of covering more results. But at 1% you’d need a dividend of $1,000 just to win $10.
By position
Choose “By position” to pick separate horses for each place, like one horse for first, three for second and four for third. With the box ticked, the calculator assumes your earlier picks also appear in the later lists, as they normally do. Untick it if the lists don’t overlap at all. For multi-race exotics, the quaddie calculator uses the same flexi maths.
Exotics are long shots by design. Set your outlay first, then let the flexi follow. Gambling Help Online is free and confidential, any time of day.