Craps Prop Bet Keys: Dealer Payout Math Explained
Dealer math · Horn and C&E keys · Standard 30/15 paytable
Prop-bet keys are mental shortcuts dealers use to calculate multi-part proposition payouts. They work only when you know the paytable, distinguish profit from total return, and account for the losing pieces of a split wager.
Paytable used on this page: 2 and 12 pay 30 to 1; 3 and 11 pay 15 to 1; Any Craps pays 7 to 1; Any 7 pays 4 to 1. Some dealer schools describe those same straight-up returns as 31-for-1 and 16-for-1 because the returned winning wager is included. Verify the layout before using a key.
“To 1” versus “for 1”
| Displayed payout | $1 profit | Winning $1 returned | Total value |
|---|---|---|---|
| 30 to 1 | $30 | $1 | $31, sometimes called 31-for-1 |
| 15 to 1 | $15 | $1 | $16, sometimes called 16-for-1 |
| 7 to 1 | $7 | $1 | $8, sometimes called 8-for-1 |
| 4 to 1 | $4 | $1 | $5, sometimes called 5-for-1 |
A dealer key often starts with the total return, then subtracts the losing pieces while leaving the winning unit working. A player asking “How much did I win?” usually wants net profit. State which number you are calculating.
Straight-up 2, 3, 11, and 12
| Total | Standard profit | Return including wager | $6 example |
|---|---|---|---|
| 2 or 12 | 30 × bet | 31 × bet | $180 profit; $186 including wager |
| 3 or 11 | 15 × bet | 16 × bet | $90 profit; $96 including wager |
C&E key
A standard C&E splits the total equally between Any Craps and 11. With a $2 C&E, $1 is on each side.
| Result | Winning component | Losing component | Net profit on total C&E |
|---|---|---|---|
| 2, 3, or 12 | Any Craps wins 7 × half | Eleven half loses | 3 × total bet |
| 11 | Eleven wins 15 × half | Any Craps half loses | 7 × total bet |
Examples: a $2 C&E nets $6 on craps or $14 on 11. A $10 C&E nets $30 on craps or $70 on 11. A $5 C&E requires $2.50 components; many dollar games will not accept or will handle that fraction differently, so do not assume the key applies.
High-Low key
High-Low splits equally between 2 and 12. If the total wager is B, each side is B/2. One side wins 30 units while the other loses one:
net profit = 29 × half the total bet = 14.5 × total bet
For a $20 High-Low, $10 is on 2 and $10 on 12. A winning side earns $300; the other $10 loses, leaving $290 net profit. The winning $10 wager remains yours.
Horn bet key
A proper Horn bet divides into four equal units on 2, 3, 11, and 12. For a $4 Horn, each number has $1.
| Horn result | Winning profit | Three losing units | Net profit | Key on total Horn |
|---|---|---|---|---|
| 3 or 11 | 15 units | −3 units | 12 units | 3 × total bet |
| 2 or 12 | 30 units | −3 units | 27 units | 6¾ × total bet |
A $4 Horn therefore nets $12 on 3/11 or $27 on 2/12. A $20 Horn nets $60 on 3/11 or $135 on 2/12.
Horn High: general method
Horn High uses five equal units: one on each Horn number plus an extra unit on the called number. A $5 Horn High 12 is $1 each on 2, 3, and 11, and $2 on 12.
| $5 Horn High 12 result | Calculation | Net profit |
|---|---|---|
| 12 (called high number) | $2 × 30 − $3 losers | $57 |
| 2 (other high number) | $1 × 30 − $4 losers | $26 |
| 3 or 11 | $1 × 15 − $4 losers | $11 |
For Horn High 2, the same rows apply with 2 and 12 exchanged. If the high number is 3 or 11, the called low number has two units: it nets $27; the other low number nets $11; either 2 or 12 nets $26.
Whirl or World bet key
A Whirl/World is five equal units: a four-unit Horn plus one unit on Any 7. Under a standard 4-to-1 Any 7 payout:
| Result | Net key | $15 example |
|---|---|---|
| 7 | Push: Any 7 profit offsets four losing Horn units | $0 |
| 3 or 11 | 11 × one unit | $33 |
| 2 or 12 | 26 × one unit | $78 |
For a $15 Whirl, one unit is $3. That produces 11 × $3 = $33 on 3/11 and 26 × $3 = $78 on 2/12.
Three-Way Craps key
Three-Way Craps splits equally among 2, 3, and 12.
| Result | Net per unit | Key on total bet | $12 example |
|---|---|---|---|
| 2 or 12 | 30 − 2 = 28 units | 9 × bet + one unit | $112 |
| 3 | 15 − 2 = 13 units | 4 × bet + one unit | $52 |
Three-Way 7 key
At a table that books a Three-Way 7 as three equal hop wagers—1–6, 2–5, and 3–4—each component covers both dice orders and commonly pays 15 to 1. Confirm that definition and paytable before using the key; grouped-hop names and payouts are house-dependent.
Let the total bet be B and each component be u = B/3. Any 7 wins 15u on one component while the other two units lose, so the net is 13u:
net profit = 13 × one-third of the total bet = 4 × total bet + one-third of the total bet
| Total Three-Way 7 | Each component | Calculation | Net profit on any 7 |
|---|---|---|---|
| $3 | $1 | $15 winner − $2 losers | $13 |
| $75 | $25 | $375 winner − $50 losers | $325 |
| $138 | $46 | $690 winner − $92 losers | $598 |
Under that 15-to-1 paytable, the grouped bet covers all six ways to roll 7 but still has an 11.11% house edge: it wins one roll in six and loses five rolls in six. The shortcut speeds a payoff; it does not improve the bet.
Breakage and improper units
A Horn amount not divisible by four and a Horn High amount not divisible by five create fractional components. Some casinos reject the wager, some round or book it under a posted procedure, and some require the player to add a chip. The clean dealer response is to follow the house procedure—not improvise from a generic internet key.
Rounding must be priced separately from the exact key. Losing $0.75 to rounding, receiving it or having the amount rejected are materially different outcomes. Ask the floor how the house treats breakage before calling an amount that creates fractional units.
Dealer learning order
- Memorize the actual straight-up paytable.
- Understand wager units and which components lose.
- Learn hand positioning, game protection, booking, and communication.
- Use a key only after you can reconstruct the payoff from first principles.
- Verify unusual amounts against the house procedure.
Keys improve speed; they do not replace procedural accuracy. Players can use the same arithmetic to check a payout, but should not interrupt settlement unless the amount is genuinely wrong.
For wager maximums, see Craps Table Limits. For the standard paytable and house edges, use the Craps Payout Table.
Audit a Horn payout from layout to rack
Suppose $20 is divided into $5 each on 2, 3, 11, and 12, and 12 rolls. The winning $5 earns $150 at 30 to 1. The other three $5 components lose, so the net profit on the complete $20 Horn is $150 − $15 = $135. That is the table’s 6¾-times-total key.
If every component is taken down, the player receives the $150 profit plus the surviving $5 wager, or $155 to the rack. Comparing that return with the original $20 outlay again gives $135 net profit. The $155 return should not be called a $155 win because $5 of it is the player’s returned stake.
If the player wants another $20 Horn working, $15 must replace the three losing components while the winning $5 stays in place. The rack can increase by $135 and the restored $20 remains exposed to the next roll. This chip-by-chip check reaches the same net result as the shortcut and makes the wager state explicit.
Use the High-Low key to check return and repeat status
A $20 High-Low has $10 on 2 and $10 on 12. If 12 wins at 30 to 1, its component pays $300 profit and the other $10 loses. Taking everything down returns $310 including the surviving $10 stake, for $290 net profit over the original $20. The 14.5-times-total key calculates that $290 profit, not the $310 return.
Repeating the full $20 High-Low uses $10 of the winning payment to restore the losing 2 component. Collect $290 with $20 on the layout. Leaving only the winning $10 on 12 instead creates a different next-roll wager. An exact key does not authorize fractional units or override table minimums; name the package and confirm whether both sides renew. The payout auditor can check the straight-up component before you subtract the other losses.
