Owns
Wheel pockets, winning pockets, standard roulette payout, win probability, house edge, expected loss per spin, planned-spin expected loss and one practice spin.
Roulette odds and expected-loss tool
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Last updated May 18, 2026
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Formula reviewed May 18, 2026
Roulette Calculator
Calculate roulette win probability, payout, house edge, expected loss and a single practice spin for common bet families. This is an educational math tool, not a betting-system backtester and not a way to predict a live wheel.
This page owns one job: translating roulette wheel type, bet family, stake and planned spin count into probability, payout and expected-loss context.
Use it to compare European, American and French-style even-money rules, understand why the 00 pocket matters, and practice one spin. Do not use it to justify Martingale, chase a loss, verify a casino, or decide whether gambling is legal in your state.
What this roulette calculator owns
Does not own
Live wheel prediction, audited RNG behavior, casino legality, table availability, payout approval, bonus terms, tax treatment or progression-system proof.
Stop using it when
The result creates pressure to raise stakes, recover losses, keep spinning, deposit again, or treat a winning practice spin as a signal to play.
Disclosure, privacy and safety before the calculator
Disclosure: commercial links elsewhere on the site do not change the wheel probabilities, payouts, validation rules, warnings or formula limits on this page.
Privacy: this calculator runs in your browser. Do not enter account IDs, document numbers, SSN, card numbers, bank details, login credentials, home address, private ticket screenshots or operator account data.
Responsible-play boundary: if a result makes you want to chase, increase stakes, extend a session, recover a loss or deposit again, stop. Call or text 1-800-MY-RESET for confidential support. State-specific resources may vary.
Run the roulette calculator
Visual roulette layout and multi-chip coverage
Click straight-number pockets to place practice chips. Multiple clicks on the same pocket create duplicate coverage. This module shows total stake, covered pockets, hit probability and the net result if each selected pocket lands.
Each click adds one straight-number chip. This is layout math, not a recommended staking plan.
The visual grid updates zero pockets and house-edge labels. It does not verify a specific casino table.
No layout chips placed yet.
Covered pockets0
Total straight chips0
Total stake$0.00
Hit probability0.00%
Expected loss per spin$0.00
Duplicate coverageNone
Wheel cost label2.70%
Scope limitStraight chips only
| Pocket lands | Chip on pocket | Other chips lost | Net result |
|---|---|---|---|
| Place chips to see the net result by pocket. | |||
Session pace and hourly expected-loss check
This module estimates total wagered and expected loss from pace. It is not a session prediction and does not mean a session is safe.
Use French even-money only when the rule is visible and applies to the bet you plan to model.
Pace check ready.
Pace result
Total spins modeled60
Total amount wagered$600.00
Expected loss per hour$16.22
Expected loss for session$16.22
If this number creates pressure to chase or extend play, stop and use the reality-check route.
At least once in N spins probability
Use this to understand how often a bet might hit at least once across a planned number of spins. It does not mean the hit is due, and it does not change the next-spin probability.
At-least-once probability ready.
At least once result
Single-spin hit probability2.70%
At least one hit93.54%
Miss every spin6.46%
A high at-least-once probability does not make the next spin due and does not remove expected loss.
La Partage / En Prison rule checker
Check before relying on a reduced edge
Rule confidence output
Do not rely yet. Reduced-edge rules need visible wording before you model them.
This is a rule-evidence checklist, not legal advice, operator approval, or a guarantee that a payout will be handled a certain way.
Table-rule evidence packet
What to verify before relying on table math
Evidence confidence output
Do not rely yet. Save the visible wheel type, payout table and table limits before using the result.
Streak and gambler's fallacy check
What does a streak mean?
No-signal output
A five-spin red sequence can happen, but it does not change the next spin probability.
Past spins do not make red, black, a number or a zero "due." If a streak makes you want to increase stake, stop.
Input definitions
| Input | Use it for | Limit |
|---|---|---|
| Wheel type | Choosing European, American or French-style edge assumptions. | It does not verify the actual table, casino, jurisdiction or live wheel. |
| Bet family | Selecting the standard payout and number of winning pockets. | It does not model every call bet, neighbor bet, side bet or table-specific restriction. |
| Selected number, dozen or column | Making the practice spin and copied result match the selected bet. | Selection changes which pocket wins, not the house edge for the bet family. |
| Stake per spin | Calculating payout math and expected loss per spin. | It is not a recommended stake and should never use money needed for essentials. |
| Practice bankroll | Showing exposure and one simulated bankroll update. | It is not a bankroll plan, survival probability or permission to continue spinning. |
| Planned spins | Scaling expected loss across a hypothetical session length. | It is not a forecast of what will happen in your session. |
| Layout chips | Comparing multiple straight-number chips and duplicate coverage. | It does not model call bets, neighbor bets, progressive systems or table-limit failure. |
| Spins per hour / session length | Estimating total wagered and expected cost from pace. | It is not a prediction of session outcome or a reason to extend play. |
| At-least-once spins | Estimating the chance of at least one hit and the chance of missing every spin across N spins. | It does not make the next spin due or improve the bet. |
| Evidence checks | Separating visible table-rule evidence from assumptions. | It is not operator approval, legal advice or payout assurance. |
How to read the result
| Result label | What it means | What it does not mean |
|---|---|---|
| Win probability | Winning pockets divided by total pockets for the selected wheel. | It does not predict the next spin or prove a wheel is due. |
| Standard net payout | The standard net payout for the selected roulette bet family. | It does not include bonuses, table limits, disputes, taxes or operator approval. |
| House edge / expected loss rate | The long-run mathematical disadvantage under the selected wheel assumption. | It does not guarantee a loss or a win in a short session. |
| Expected loss for planned spins | Stake multiplied by the edge and planned spin count. | It is not a stop-loss plan, bankroll recommendation or recovery strategy. |
| Single-spin outcome | A browser-only practice spin for learning the payout path. | It is not evidence that a live wheel, RNG or table will behave the same next. |
Formula and assumptions
Probability
Winning pockets divided by total wheel pockets. European/French wheels use 37 pockets; American uses 38 pockets; triple-zero uses 39 pockets.
Expected loss
Stake x house-edge rate x planned spins. This is a long-run average estimate, not a session forecast.
Payout
Standard net payout odds by bet family: straight 35:1, split 17:1, street 11:1, corner 8:1, six line 5:1, dozen/column 2:1 and even-money 1:1. Basket/top-line exceptions use their visible table payout.
European vs American vs French-style roulette
| Wheel | Pockets | Baseline edge | What changes |
|---|---|---|---|
| European single-zero | 37 | 2.70% | One zero pocket. Standard roulette payouts create a smaller edge than American roulette. |
| American double-zero | 38 | 5.26% | Adds 00. The extra losing zero pocket increases the edge across standard bet families. |
| French-style la partage | 37 | 2.70%, or about 1.35% on even-money bets with la partage | This model applies the reduced edge only to red/black, even/odd and low/high bets. |
| Triple-zero roulette | 39 | 7.69% | Adds 000. The third zero increases the baseline cost when standard payouts are used. |
Supported roulette bet families
| Bet family | Winning pockets | Net payout | Common mistake |
|---|---|---|---|
| Straight | 1 | 35 to 1 | Treating a rare hit as proof of a repeatable edge. |
| Split | 2 | 17 to 1 | Forgetting the wheel edge remains even when more numbers are covered. |
| Street | 3 | 11 to 1 | Confusing a larger hit rate with a better expectation. |
| Corner | 4 | 8 to 1 | Ignoring table layout restrictions on real tables. |
| Six line | 6 | 5 to 1 | Assuming more coverage removes variance. |
| Red/black, even/odd, low/high | 18 | 1 to 1 | Zero and 00 still lose; la partage rules must be verified before assuming reduced loss. |
| Dozen or column | 12 | 2 to 1 | Treating all dozens or columns as the same without selecting which one is being modeled. |
| Basket/top-line exception | American: 5; triple-zero: 6 | Often 6 to 1 on American basket; 5 to 1 on six-number top line where offered | Assuming this exception has the same edge as standard roulette bets. |
Worked examples
European red, $10 stake
Red covers 18 of 37 pockets. Win probability is 48.65%, net payout is $10 on a win, and long-run expected loss is about $0.27 per spin.
American straight, $5 stake
A straight number covers 1 of 38 pockets. Win probability is 2.63%, net payout is $175 on a win, and expected loss is about $0.26 per spin.
French-style even-money, $20 stake
With la partage modeled, the effective loss rate for even-money bets is about 1.35%, so expected loss is about $0.27 per spin. The rule must be visible before relying on it.
Triple-zero straight, $5 stake
A straight number covers 1 of 39 pockets. Win probability is 2.56%, net payout is $175 on a win, and expected loss is about $0.38 per spin.
Why this is not a Martingale or system backtester
No doubling engine
The page does not model Martingale, Fibonacci, D'Alembert, Labouchere, cancellation systems, stop rules, table limits or bankroll exhaustion.
No risk-of-ruin promise
A planned-spin expected loss estimate is not a certified survival probability or session outcome prediction.
No recovery-loss support
If the reason for changing stake is to win back money, use the reality-check route instead of changing calculator inputs.
Roulette myths this calculator refuses
| Myth | Correction | Best route |
|---|---|---|
| Red is due after five blacks. | Next-spin probability is unchanged under the selected wheel model. | Use the streak checker. |
| Covering more numbers lowers the house edge. | It changes hit rate and payout size, not the standard wheel edge. | Check the bet-family table. |
| Martingale beats roulette. | Table limits, bankroll exhaustion and loss recovery pressure remain. | Use the reality-check tool. |
| French roulette is always 1.35%. | The reduced label applies only to eligible even-money bets with visible rule wording. | Use the rule checker. |
| Triple-zero just adds one more number. | It raises baseline expected loss to about 7.69% when standard payouts apply. | Compare wheel types. |
Roulette calculator vs RTP calculator vs bankroll planner
| Question | Roulette Calculator | RTP Calculator | Bankroll Planner |
|---|---|---|---|
| What does this roulette bet pay? | Yes | No | No |
| What is expected loss per spin? | Yes | Yes, for generic house-edge conversion | No |
| What is my session budget? | No | No | Yes |
| Can I survive a Martingale? | No | No | No. Use Reality Check. |
| Is this table legal in my state? | No | No | No. Use state guides. |
What to save before relying on a roulette result
- Wheel type and whether 00 is present.
- Visible payout table for the exact bet family.
- Whether la partage or en prison applies, and to which bets.
- Table minimum, maximum and any bet-family restrictions.
- Whether 000, basket/top-line exceptions, or double-zero surrender rules are visible.
- Stake, practice bankroll, planned spins and stop point.
- For multi-chip coverage: selected pockets, duplicate chips, total stake and copied outcome table.
- Support route if the calculation creates urgency, chasing or pressure to play longer.
Formula registry
| Tool name | Roulette Calculator |
|---|---|
| Tool type | Calculator plus single-spin simulator |
| Formula owner | The Playbook USA Tools Team |
| Formula version | Roulette Probability Model v2.2 |
| Formula reviewed | May 18, 2026 |
| Inputs | Wheel type, bet family, selected number/dozen/column where relevant, stake, practice bankroll, planned spins, layout chips, pace inputs, at-least-once inputs, rule/evidence checks and streak inputs. |
| Outputs | Winning pockets, total pockets, probability, payout, house-edge label, expected loss per spin, planned-spin expected loss, multi-chip coverage, at-least-once probability, session pace cost, rule confidence, evidence confidence, streak no-signal note and one simulated spin result. |
| Assumptions | Standard roulette payouts; independent spins; straight-chip coverage for the visual layout; no dealer signature, no biased-wheel claim, no certified RNG simulation. |
| Known exclusions | Progression systems, real wheel prediction, audited RNG, casino-specific table rules, legality, tax, bonus terms, payout approval, user suitability, live wheel tracking and correlated betting behavior. |
| Review cadence | Quarterly, or sooner if tool scope, visible formula or responsible-gambling routing changes. |
QA test matrix
| Case | Input | Expected output |
|---|---|---|
| European straight | European, straight, $5 | 1 of 37 pockets, 2.70% probability, 35:1 payout, $0.14 expected loss. |
| American red | American, red, $10 | 18 of 38 pockets, 47.37% probability, 5.26% expected-loss rate. |
| French even-money | French-style, even, $20 | 18 of 37 pockets, 48.65% probability, about 1.35% modeled loss rate. |
| Triple-zero straight | Triple-zero, straight, $5 | 1 of 39 pockets, 2.56% probability, 7.69% expected-loss rate. |
| American basket | American, basket/top-line exception, $5 | 5 of 38 pockets, 6:1 payout, about 7.89% expected-loss rate. |
| Decimal stake | European, split, $2.50 | Currency formats to cents; probability remains 2 of 37 pockets. |
| Invalid stake | Stake 0 or negative | Accessible validation message and no spin/calculation update. |
| Invalid planned spins | 0, negative, decimal, or more than 1,000 spins | Accessible validation message; result remains educational and unchanged. |
| High planned spins | 1,000 planned spins | Expected loss scales from the per-spin loss without claiming a session forecast. |
| Stake over bankroll | Stake greater than practice bankroll | Exposure warning; calculation remains educational and spin is blocked. |
| American straight 00 | American wheel, straight, 00 | 00 appears as a selectable straight pocket only on the American wheel. |
| La partage boundary | French-style, dozen or straight | Reduced 1.35% label is not applied because la partage is modeled only for even-money bets. |
| Multi-chip coverage | Two chips on 17, one chip on 20 | Two covered pockets, three total chips, duplicate coverage warning and per-pocket net-result rows. |
| Session pace | $10 stake, 60 spins/hour, 2 hours, American wheel | Total wagered $1,200 and expected session loss about $63.16. |
| At least once | European straight, 100 spins | At least one hit about 93.54%; miss every spin about 6.46%; no-due warning appears. |
| Evidence packet | All table-rule evidence boxes checked | Higher-confidence evidence output and copyable checklist without private data. |
| Streak check | European red, 5 in a row | Sequence probability shown; next-spin probability remains 48.65% and no-signal warning appears. |
| Progression request | User wants Martingale or recovery-loss logic | Tool refuses scope and routes to bankroll/reality-check support. |
| Copy/download packet | Click Copy result or Download TXT | Summary includes assumptions and safety limits, without personal or account data. |
| Public fixtures | /tools/roulette/test-fixtures.json | Machine-readable expected outputs mirror the visible QA cases. |
Source registry
Internal formula registry
Roulette Probability Model v2.2: pocket count, payout odds, expected-loss labels, multi-chip coverage, at-least-once probability, pace math, evidence checks, streak checks and QA cases.
Visible roulette rules
This page relies on standard published roulette payout conventions. Specific table rules must be checked before play.
Public fixtures
Formula fixture route: /tools/roulette/test-fixtures.json. Fixture cases are educational verification assets, not betting advice.
Responsible-gambling routing
Help routing checked May 18, 2026. Call or text 1-800-MY-RESET. State-specific resources may vary.
When this tool stops being the right owner
Need legality or state status?
Roulette math does not verify whether a product is available or legal for your location.
Use state guidesNeed session limits?
Use bankroll planning before session play, not after a practice spin changes mood or stake pressure.
Use the bankroll plannerFeeling pressure?
If roulette practice creates urgency or chasing, stop using calculators and move to support.
Use the reality-check toolMaintained and reviewed by
Maintained by The Playbook USA Tools Team.
Review scope: pocket counts, standard payout labels, expected-loss formulas, validation behavior, no-JS fallback, responsible-gambling stop gates, privacy warnings and no-News navigation.
Roulette calculator FAQ
Can this roulette calculator predict a spin?
No. It calculates probability and expected-loss context from the selected wheel and bet family. The spin button is practice only.
Why does American roulette have a higher house edge?
American roulette adds 00. Standard payouts do not increase for the extra pocket, so the house edge rises from about 2.70% to about 5.26%.
Does la partage make roulette beatable?
No. It can reduce loss rate on eligible even-money bets when zero lands, but it does not create a guaranteed edge or positive expectation.
Can I use this for Martingale or other systems?
No. This root page does not model doubling systems, table limits or bankroll exhaustion. Do not use the calculator for recovery-loss behavior.
Can the visual layout model multiple roulette chips?
Yes. It can add multiple straight-number chips, show duplicate coverage, total stake, covered pockets and the net result if each selected pocket lands. It does not model call bets, neighbor bets or progression systems.
Does a streak make red, black or a number due?
No. The streak checker shows sequence probability, then keeps the next-spin probability unchanged under the selected wheel model.
Does the calculator cover triple-zero roulette?
Yes. The updated model includes a triple-zero wheel with 39 pockets and a 7.69% standard expected-loss rate when standard payouts apply.
What does at least once in N spins mean?
It estimates the chance that the selected bet hits at least one time across a planned number of spins, plus the chance it misses every spin. It does not make the next spin due.
What should I save before relying on roulette table rules?
Save the visible wheel type, payout table, special zero rules, table limits, special exceptions and a screenshot without private account, card, bank, identity or ticket data.
Changelog
May 18, 2026: upgraded to Roulette Probability Model v2.2; added expected-loss calculator, at-least-once probability module, triple-zero support, basket/top-line exceptions, visual straight-chip layout, multi-chip coverage table, session pace module, table-rule evidence packet, La Partage/En Prison checker, roulette myths table, intent map, streak/gambler's fallacy check, public fixtures, scenario presets, input definitions, result interpretation, copy/download summary, expanded QA matrix, source registry, privacy/RG boundaries, FAQ schema, no-JS fallback and no-News navigation.
Apr 24, 2026: earlier single-spin simulator with European/American wheel comparison and basic bet families.
Responsible gambling help
For confidential help in the U.S., call or text 1-800-MY-RESET. Existing access points may remain active, and state-specific resources may vary.
Help routing checked: May 18, 2026. Re-check NCPG phone, text, chat and state-resource wording before each quarterly tools update.