How to play craps, and the real odds
Craps has the loudest table and the longest list of bets, which makes it look impossible. It isn't: a handful of bets do all the work, and one of them, free odds, is the only wager in the casino with zero house edge. This guide covers how the game flows, what each bet really costs, and how to play it cheaply: with the numbers computed by our own reviewed engine.
What this guide covers
We'll start with how a round actually flows (the come-out and the point), walk through the core bets and what each pays, then get to the one idea that makes craps worth learning: free odds, and how adding them drags your effective edge toward zero. Every figure comes from our analytic solver, not a rule of thumb.
1. How craps works
One player (the "shooter") rolls two dice; everyone bets on the outcome. A round has two phases:
- The come-out roll. The first roll. A 7 or 11 wins even money for the pass line; 2, 3, or 12 ("craps") loses it; any other number: 4, 5, 6, 8, 9, or 10 : becomes the point, and a marker (the "puck") flips to ON.
- The point phase. The shooter keeps rolling until they either roll the point again (the pass line wins) or roll a 7 first (a "seven-out"; the pass line loses and the dice pass to the next shooter).
That's the whole engine. The don't pass bet is the mirror image, it wins when a 7 comes before the point, and come / don't come bets work exactly like pass/don't but can be started on any roll after a point is set, traveling to their own number. You can watch all of this play out, one roll at a time, on our free table with "Explain this roll" turned on.
2. The core bets & payouts
Here's the core menu, with the win chance and house edge computed from our engine:
| Bet | Pays | Win chance | House edge |
|---|---|---|---|
| Pass Line / Come, the basic line bet, with the dice | 1:1 | 49.29% | 1.41% |
| Don't Pass / Don't Come, against the dice (12 is barred) | 1:1 | 47.93% | 1.36% |
| Free Odds, behind a line/come bet, true odds | true | n/a | 0.00% |
| Place 6 / 8, bet a number rolls before a 7 | 7:6 | 45.45% | 1.52% |
| Place 5 / 9, bet a number rolls before a 7 | 7:5 | 40.00% | 4.00% |
| Place 4 / 10, bet a number rolls before a 7 | 9:5 | 33.33% | 6.67% |
| Field, one-roll bet on 2 3 4 9 10 11 12 | 1:1 * | 44.44% | 5.56% |
* The field pays even money on 3, 4, 9, 10, 11 and double on 2 and 12 (some tables pay triple on 12, which lowers the edge to 2.78%). "House edge" is per wager; the don't side includes the bar-12 push.
3. Free odds: the only 0% bet
Once a point is established, you can put an additional bet "behind" your pass line called free odds. It pays true odds, exactly the real probability, so it has a house edge of 0%. The catch: you can only make it after a point is set, and only as a multiple of your line bet (the "3-4-5×" cap is the modern standard: 3× on 4/10, 4× on 5/9, 5× on 6/8).
Because the odds portion is free, blending it with your line bet lowers the combined edge on everything you wager. A pass line alone is 1.41%; backed with 3-4-5× odds the combined edge on total action drops to about 0.37%, and at a 10× table to roughly 0.18%. There's nothing else like it in the building:
| Bet | Pays | Win chance | House edge (per wager) | Loss / $100 |
|---|---|---|---|---|
| Don't Pass / Don't Comebar 12, 12 pushes | 1:1 | 47.93% | $1.36 | |
| Pass Line / Comethe line bet | 1:1 | 49.29% | $1.41 | |
| Place 6 / 8rolls before a 7 | 7:6 | 45.45% | $1.52 | |
| Place 5 / 9rolls before a 7 | 7:5 | 40.00% | $4.00 | |
| Fieldone-roll: 2 3 4 9 10 11 12 | 1:1 · 2&12 dbl | 44.44% | $5.56 | |
| Place 4 / 10rolls before a 7 | 9:5 | 33.33% | $6.67 | |
| Free odds (take / lay)true odds behind a line/come bet | true | n/a | $0.00 |
The odds effect: free odds drag your edge toward zero
A pass line alone is 1.41%. Free odds pay true odds (0% edge), so backing the line spreads that same expected loss over far more action; the combined edge on everything you wager falls fast:
Edge on total action (flat bet + the odds you'd wager once a point is set). With 3-4-5× odds the pass line's effective edge is just 0.37%, the cheapest action in the casino. Try it live in the Play and Simulate tabs.
The field's two variants
- 2 & 12 both pay 2:1 (common)5.56%
- 12 pays 3:1 (better tables)2.78%
The field looks friendly, it wins on seven of eleven totals, but it loses on 5, 6, 7, 8, which are the most common rolls. Even the better 3:1 version trails the line bets.
Why place 6/8 beats place 4/10
- Place 6 / 8: pays 7:61.52%
- Place 5 / 9: pays 7:54.00%
- Place 4 / 10: pays 9:56.67%
6 and 8 are the easiest numbers to roll before a 7, so their place bet is priced closest to fair. The 4 and 10 are the hardest, and the casino's 9:5 payout shorts them the most.
4. Why the center bets cost more
The bets shouted across the table are the expensive ones. Place 4 and 10 cost 6.67%; the field, which looks friendly because it wins on seven different totals, still costs 5.56%, because it loses on 5, 6, 7, and 8, which are the most common rolls. The not-yet-modeled proposition bets in the center (hardways, any-seven, horn) are worse still, several above 11%.
The pattern is simple: the more exciting and the bigger the advertised payout, the more it usually costs you. The cheap bets are the boring ones: the line with odds, and place 6/8 at 1.52%. See it ranked in the table above, and watch a small edge grind a bankroll down in the interactive house-edge model.
5. “Working” and “off”
Not every bet is live on every roll. By default, on a new come-out roll your place bets and your come odds are off, they can't win or lose, while your flat pass/come bets stay working. This is a casino convention (and it's why a come-out 7 can lose your come bet but merely return its odds). Our engine applies it exactly. (Whether odds work on the come-out is one of the things that varies by table.)
6. Bankroll & variance
Craps swings hard: a hot shooter can string together many numbers, and a quick seven-out can wipe a felt full of bets in one roll. Free odds in particular add variance without adding edge: your average result is the same, but the ups and downs get bigger. That's fine if it's entertainment and your bets are small relative to your bankroll; it's dangerous if you're chasing.
No betting system beats the dice: they have no memory, and "due" numbers aren't due. The only real edge-management is bet selection (line + odds, maybe place 6/8) and bankroll management (small bets, hard limits). Watch the math play out on our Simulate tab.
7. Next steps
How this simulation works
- Rules modeled
- Two-die craps with the come-out → point state machine. Core bets: Pass / Don't Pass (bar 12), Come / Don't Come, Free Odds (take and lay), Place (4,5,6,8,9,10), and the Field. Free-odds cap default 3-4-5×; field default pays 2:1 on both 2 and 12. Stakes are whole dollars with the traditional bet units.
- Assumptions
- Two fair, independent dice. Win chance is the probability the bet wins on a resolution. House edge is per initial wager (the don't side includes the bar-12 push). Free odds are true odds (0%); the combined line+odds figure is measured on total action. Come odds and place bets are off on the come-out by default.
- Mathematical basis
- Every odd and edge is computed at build time by our craps analytic solver (exact bigint rationals; one-roll enumeration for the field, per-resolution ratios for place bets, the come-out distribution plus a per-point geometric series for line/come bets, true odds for free odds), the displayed source of truth. Reference edges: pass/come 1.41%, don't 1.36%, place 6/8 1.52% · 5/9 4.00% · 4/10 6.67%, field 5.56% (2:1) / 2.78% (3:1 on 12), free odds 0%, pass + 3-4-5× ≈ 0.37% on total action.
- Engine version
- craps engine 1.0
- Validation
- Unit-tested (every bet's edge, the per-initial-wager vs per-resolution distinction, the full come-out→point lifecycle with come bets traveling independently, the working/off matrix, place stay-up, the stake-aware combined-odds identity across every cap, invariants, seeded reproducibility, SE-scaled convergence).
- Last reviewed
- Independently reviewed for math and code correctness; every reported finding was addressed and regression-tested.
All Craps guides →; the full library, from the basics to the edge cases.