Calculate key bet costs for exacta, trifecta, and superfecta wagers. Use one horse in a fixed position with others filling remaining spots.
Key horse must finish first; others can fill remaining positions.
Base stake for each combination
Key Bet Cost
$8
4 combinations
Box Cost
$40
Full 5-horse box
Savings
$32
80% less than box
Exacta key first #3 over 4 horses:
4 combinations
4 × $2 = $8
Quick-start with common scenarios
Key betting uses one horse in a fixed position while others fill remaining spots. Exacta key first with 4 others = 4 combos. Trifecta key first with 4 others = 4×3 = 12 combos. A $2 exacta key first with #3 over 4 horses costs just $8 vs $40 for a full 5-horse box.
| Bet Type | Key First (4 others) | 5-Horse Box | Savings |
|---|---|---|---|
| $2 Exacta | 4 = $8 | 20 = $40 | $32 (80%) |
| $1 Trifecta | 12 = $12 | 60 = $60 | $48 (80%) |
| $0.10 Superfecta | 24 = $2 | 120 = $12 | $10 (80%) |
A key bet uses one horse in a fixed position while other horses fill the remaining positions. For example, a $2 exacta key with horse #3 first over horses 1, 5, 7 creates combinations: 3-1, 3-5, 3-7 (3 bets = $6).
"Key first" means your horse must win and others can run second. "Key last" means your horse must run second and others can win. "Key with" covers both directions, doubling the combinations.
For trifecta key first with n other horses: cost = n × (n-1) × stake. Key #5 first with horses 1,2,3,4: 4 × 3 = 12 combinations. At $2 = $24. This is much cheaper than a 5-horse box (60 combinations = $120).
Use key bets when you have one horse you strongly believe will finish in a specific position but are unsure which horses will fill the other spots. If you're uncertain about all positions, a box is more appropriate despite the higher cost.
Yes, you can key two horses in specific positions (called a "part-wheel"). For a trifecta, you might key #3 first, #7 second, with horses 1,2,4,5 in third. This creates just 4 combinations instead of a full box.