Roulette Single Number Calculator: The 35:1 Dream

Straight-up bets on single numbers pay 35:1—the highest payout on the roulette table. Our calculator shows the true probability, expected value, and why despite the excitement, the house edge remains unchanged.

What Is a Straight-Up Bet?

A straight-up bet places your chips directly on one number. If that exact number hits, you win 35:1. The probability is 1/37 (European) or 1/38 (American). It's the highest-variance, highest-payout bet in roulette.

Quick Answer: Single number probability: 2.70% (European) or 2.63% (American). Payout: 35:1. True odds: 36:1 (European) or 37:1 (American). House edge: 2.70% (European) or 5.26% (American). Same edge as all other roulette bets. The high payout is exciting but mathematically equivalent to betting red/black over time.

How to Use Our Calculator

Use the Single Number Calculator →

Enter bet details to see probability and expected value.

Step-by-Step Instructions

1. Select Roulette Type: European or American

2. Enter Bet Amount: Per number

3. Choose Number: Your selection

4. View Win Probability: Exact percentage

5. Calculate Expected Value: Average return

Input Fields Explained

Field	Description	Example
Roulette Type	European/American	European
Bet Amount	Per number	$5
Selected Number	Your pick	17
Win Probability	1/37 or 1/38	2.70%
Payout	On win	$175
House Edge	Casino advantage	2.70%
Expected Loss	Per bet	$0.14

Single Number Probability

European Roulette

Numbers: 0-36 (37 total)
Your number: 1 way to win
Other numbers: 36 ways to lose

Probability: 1/37 = 2.703%
Odds against: 36:1

Payout: 35:1
Shortchange: 1 unit
House edge: 1/37 = 2.70%

American Roulette

Numbers: 0, 00, 1-36 (38 total)
Your number: 1 way to win
Other numbers: 37 ways to lose

Probability: 1/38 = 2.632%
Odds against: 37:1

Payout: 35:1
Shortchange: 2 units
House edge: 2/38 = 5.26%

Expected Value Calculation

European Single Number

$5 bet on any single number:

Win: $175 (35:1)
Probability: 2.703%

Lose: -$5
Probability: 97.297%

EV = ($175 × 2.703%) - ($5 × 97.297%)
EV = $4.73 - $4.86 = -$0.13

House edge: 2.70%

American Single Number

$5 bet on any single number:

Win: $175 (35:1)
Probability: 2.632%

Lose: -$5
Probability: 97.368%

EV = ($175 × 2.632%) - ($5 × 97.368%)
EV = $4.61 - $4.87 = -$0.26

House edge: 5.26%

The 35:1 Reality Check

What 35:1 Means

Bet $1, win $35 + your $1 back = $36

True odds (European): 36:1
Casino pays: 35:1
Difference: 1 unit per 37 spins average

That 1-unit difference = house edge

Long-Run Math

37 spins, $1 each number:
Expected wins: 1 time
Expected losses: 36 times

Payout: 1 × $35 = $35
Losses: 36 × $1 = $36

Net: -$1 per 37 spins
Edge: 1/37 = 2.70%

Real-World Examples

Example 1: Lucky Number Session

Strategy: $10 on lucky number 7, 50 spins

Expected results:

Hits: ~1.35 times (50 × 2.70%)
Wins: 1-2 times × $350 = $350-700
Losses: 48-49 times × $10 = $480-490

Expected outcome:
1.35 × $350 - 48.65 × $10 = -$14

House takes 2.70% of $500 wagered

Example 2: Spreading Numbers

Strategy: $5 on 7 different numbers

Per spin:

Total bet: $35
Any of 7 hits: Win $175, lose $30 = +$145
None hit: Lose $35

Probability any 7 hit:
European: 7/37 = 18.92%

EV = ($145 × 18.92%) - ($35 × 81.08%)
EV = $27.43 - $28.38 = -$0.95

Same 2.70% edge on $35 total

Example 3: Neighbor Bets

Strategy: $5 on 17 and 4 neighbors (5 numbers)

Analysis:

Numbers: 2 neighbors each side + 17
Total bet: $25
Win any: +$145 (win $175, lose other $30)
Lose all: -$25

Coverage: 5/37 = 13.51%

Same house edge applies
Just different coverage pattern

Example 4: Martingale on Single Numbers

Attempt: Double bet after losses

Reality check:

Starting bet: $5
After 10 losses: $5,120 needed
After 15 losses: $163,840 needed

Probability of 15 consecutive misses:
(36/37)^15 = 65.6%

More than half the time!
Martingale on single numbers = disaster

Number Selection Myths

Hot Numbers

Belief: "17 hit 5 times, it's hot!"
Reality: Past results don't affect future
Each spin: Independent 2.70% chance
Hot numbers are coincidence

Cold Numbers

Belief: "23 hasn't hit in 100 spins, it's due!"
Reality: Still 2.70% next spin
Gambler's fallacy
Cold numbers aren't more likely

Dealer Signature

Belief: "Dealer spins consistently"
Reality: Modern wheels designed for randomness
Ball bounce is chaotic
No reliable patterns exist

Lucky Numbers

Belief: "7 is my lucky number"
Reality: All numbers equal probability
17 most bet, doesn't win more
Personal meaning ≠ better odds

Variance Considerations

Short-Term Swings

Single number betting:
Very high variance
Long losing streaks common
Occasional big wins

Expected: 1 win per 37 spins
Reality: Could be 0, 1, 2, or 5+
Distribution is very spread out

Bankroll Requirements

To survive variance on single numbers:
Need many betting units
$100 bankroll at $5 = 20 units
Could lose 20+ spins easily

Recommendation:
100+ units for single number play
Or stick to outside bets

Common Mistakes

1. Thinking Numbers Are Due

Mistake: Bet cold number expecting hit Problem: Independent events Fix: Understand randomness

2. Chasing Losses with Single Numbers

Mistake: Double up after losses Problem: Exponential bet growth, still unlikely Fix: Flat bet or don't chase

3. Betting Many Numbers for "Coverage"

Mistake: 20 numbers at $5 each for better odds Problem: $100 at risk, same house edge Fix: Fewer bets, same EV per dollar

4. Expecting 35:1 Is a Bargain

Mistake: "35:1 is a great deal!" Problem: True odds are 36:1 Fix: Understand payout vs probability

Frequently Asked Questions

Is any number luckier than others?

No. All 37 (or 38) numbers have identical probability. 17 is most bet globally but doesn't win more often.

How often will my number hit?

On average, 1 in 37 spins (European) or 1 in 38 spins (American). Could be sooner or later due to variance.

Should I switch numbers if mine hasn't hit?

Doesn't matter mathematically. Each number has the same probability every spin regardless of history.

Is betting multiple numbers better?

Same house edge per dollar bet. More coverage but more money at risk. Mathematical expectation identical.

What's the longest drought for a single number?

Theoretically unlimited. 100+ spins without hitting one number is unusual but happens. Don't bet on streaks.

Is European better for straight-up bets?

Yes, significantly. 2.70% edge vs 5.26% is nearly half the cost per bet.

Pro Tips

• European only: 35:1 pays same, odds are better

• Understand variance: Long droughts are normal

• Flat bet: Progressions don't help

• Entertainment budget: Know you'll likely lose

• No lucky numbers: All equal probability

Related Calculators

• Roulette Odds Calculator - All bet types
• Roulette Expected Value Calculator - EV analysis
• Roulette Outside Bet Calculator - Lower variance options
• House Edge Calculator - Edge comparison
• Gambling Bankroll Calculator - Session sizing

Conclusion

Single number bets offer roulette's biggest payout at 35:1—but probability remains at 2.70% (European) or 2.63% (American). Our calculator shows the exact expected value, revealing why the excitement of straight-up betting doesn't change the mathematical house edge.

Calculate Single Number Odds Now →

That 35:1 payout feels like a jackpot opportunity, but the house edge is identical to betting red/black. Our calculator proves the math: over time, you'll lose 2.70% (European) or 5.26% (American) regardless of which bet type you choose.