Roulette Split Bet Calculator: Betting Two Numbers at Once

A split bet covers two adjacent numbers on the roulette layout for a 17:1 payout. Our calculator shows exact probability, expected value, and how this inside bet compares to straight-up single number wagers.

What Is a Split Bet?

A split bet (or split) covers two adjacent numbers on the betting layout by placing your chip on the line between them. If either number hits, you win 17:1. It's a middle ground between the high risk of straight-up bets and the lower payouts of corner bets.

Quick Answer: Split bet covers 2 adjacent numbers. Pays 17:1. Probability: 5.41% (European), 5.26% (American). House edge: 2.70% (European), 5.26% (American). Place chip on line between two numbers. Same edge as all roulette bets on that wheel. Balance of coverage and payout.

How to Use Our Calculator

Use the Split Bet Calculator →

Enter your split bet to see probability and expected value.

Step-by-Step Instructions

1. Select Roulette Type: European or American

2. Choose Numbers: Two adjacent numbers

3. Enter Bet Amount: Your wager

4. View Probability: Win chance

5. Calculate EV: Expected value

Input Fields Explained

Field	Description	Example
Roulette Type	European or American	European
Split Numbers	Two adjacent	17-18
Bet Amount	Your wager	$10
Numbers Covered	The pair	17, 18
Win Probability	Hit chance	5.41%
Expected Value	Per spin	-$0.27

Valid Split Bet Combinations

Horizontal Splits

Numbers side by side:
1-2, 2-3, 4-5, 5-6, 7-8, 8-9...
10-11, 11-12, 13-14, 14-15...

Each row has 2 horizontal splits
Total: 33 horizontal splits

Vertical Splits

Numbers above/below:
1-4, 2-5, 3-6
4-7, 5-8, 6-9...
31-34, 32-35, 33-36

Each column has 11 vertical splits
Total: 33 vertical splits

Zero Splits

European (single zero):
0-1, 0-2, 0-3

American (double zero):
0-1, 0-2, 0-3
00-2, 00-3
0-00

Special positions near zeros

Probability Analysis

European Roulette

Total pockets: 37 (1-36 + 0)
Split coverage: 2 numbers
Win probability: 2/37 = 5.41%
Lose probability: 35/37 = 94.59%

Payout: 17:1
Fair payout: (37/2) - 1 = 17.5:1

House edge: 2.70%

American Roulette

Total pockets: 38 (1-36 + 0 + 00)
Split coverage: 2 numbers
Win probability: 2/38 = 5.26%
Lose probability: 36/38 = 94.74%

Payout: 17:1
Fair payout: (38/2) - 1 = 18:1

House edge: 5.26%

Expected Value Calculation

European Split Bet

$10 bet analysis:

Win: 5.41% × $170 = $9.19
Lose: 94.59% × $10 = $9.46

Net EV: $9.19 - $9.46 = -$0.27

House edge: 2.70%
Same as all European bets

American Split Bet

$10 bet analysis:

Win: 5.26% × $170 = $8.94
Lose: 94.74% × $10 = $9.47

Net EV: $8.94 - $9.47 = -$0.53

House edge: 5.26%
Double the European edge

Split vs Other Inside Bets

Comparison Table

Bet Type      | Numbers | Payout | Win% (Euro) | Edge
--------------|---------|--------|-------------|------
Straight Up   | 1       | 35:1   | 2.70%       | 2.70%
Split         | 2       | 17:1   | 5.41%       | 2.70%
Street        | 3       | 11:1   | 8.11%       | 2.70%
Corner        | 4       | 8:1    | 10.81%      | 2.70%
Six Line      | 6       | 5:1    | 16.22%      | 2.70%

All inside bets = same edge
Choose by preference

Split Position on Risk Scale

From highest risk to lowest:

Straight up (35:1) - 1 number
→ Split (17:1) - 2 numbers ←
Street (11:1) - 3 numbers
Corner (8:1) - 4 numbers
Six Line (5:1) - 6 numbers

Split: second-highest risk/reward

Betting Strategies

Single Split Focus

One split per spin:

$10 on 17-18
Win: +$170
Lose: -$10

Win rate: ~5.4%
Big wins, many losses
Same 2.70% edge

Multiple Splits

Cover section with splits:

$5 on 7-8
$5 on 8-9
$5 on 7-10
$5 on 8-11

If 8 hits: All four win!
$5 × 4 × 17 = $340

But if 7, 9, 10, 11 hit:
Only relevant splits win
$85 minus $15 = +$70

Complex coverage
Same mathematical edge

Split vs Straight-Up Equivalent

Same coverage, different approach:

Option A: $10 on 17-18 split
One bet, 17:1 payout

Option B: $5 on 17, $5 on 18
Two bets, 35:1 payout each

If 17 hits:
A: Win $170
B: Win $175 - $5 (lost 18) = $170

If 18 hits: Same $170

Mathematically identical!

Real-World Examples

Example 1: Basic Split Session

50 spins, $15 per split bet (European):

Expected wins: 2.7 (call it 3)
Expected losses: 47

Wins: 3 × $255 = $765
Losses: 47 × $15 = $705

Net: +$60

This session: lucky
Long-term: -2.70% expected

Example 2: Covering a Section

$5 each on 6 splits around number 11:

Splits: 7-8, 8-9, 8-11, 10-11, 11-12, 11-14
Total bet: $30

If 11 hits:
Three splits win (8-11, 10-11, 11-14)
3 × $85 = $255
Minus $15 losing splits = +$225

If 8 hits:
Two splits win (7-8, 8-9... wait, 8-9 and 8-11)
2 × $85 = $170
Minus $20 = +$150

Better coverage, same edge

Example 3: Comparing to Straight-Up

Budget: $20 for 10 spins:

Option A: $2 per spin on 17 straight-up
Win: $70, happens ~2.7% per spin

Option B: $2 per spin on 17-18 split
Win: $34, happens ~5.4% per spin

A: Bigger but rarer wins
B: Smaller but more frequent

Total EV: Both lose $0.54 over 10 spins
Pure preference choice

Example 4: Hedging with Splits

"Lucky numbers" 7 and 11:

Method 1: Straight-ups
$10 on 7, $10 on 11
Total: $20
If 7 hits: +$350 - $10 = +$340
If 11 hits: +$350 - $10 = +$340

Method 2: Split if adjacent... but 7-11 aren't adjacent

Alternative: Splits near each
$5 on 4-7, 7-8, 7-10
$5 on 8-11, 10-11, 11-12, 11-14

More coverage, smaller wins
Choose based on goals

Common Mistakes

1. Thinking Splits Have Better Odds

Mistake: "Two numbers = better chance" Problem: Same 2.70% house edge Fix: All bets have equal edge

2. Invalid Split Placement

Mistake: Chip between non-adjacent numbers Problem: Dealer will correct or remove Fix: Learn valid split combinations

3. Expecting Patterns

Mistake: "These two are due together" Problem: Independent random events Fix: No patterns exist

4. Playing American Over European

Mistake: Accept double zero tables Problem: 5.26% vs 2.70% edge Fix: Always choose European

Frequently Asked Questions

Which numbers can I split?

Any two numbers that share an edge on the betting layout—horizontally adjacent (like 1-2) or vertically (like 1-4).

Is a split bet better than two straight-ups?

Mathematically identical. $10 split on 7-8 equals $5 straight on 7 plus $5 straight on 8. Same coverage, same EV.

How do I place a split bet?

Put your chip on the line between two numbers. The dealer will know you're betting both.

Can I split with zero?

Yes. European allows 0-1, 0-2, 0-3. American adds 00-2, 00-3, and 0-00.

Is there a split betting system that works?

No system changes the 2.70% house edge. All split strategies eventually lose the same percentage.

What's the difference between horizontal and vertical splits?

Just the direction on the layout. Both pay 17:1 with identical probability.

Pro Tips

• European only: Half the edge

• All splits equal: No preference mathematically

• Same as two straight-ups: Just simpler

• 5.4% hit rate: Expect long gaps

• Coverage flexibility: Combine splits strategically

Related Calculators

• Roulette Odds Calculator - All bet types
• Roulette Straight-Up Calculator - Single numbers
• Roulette Corner Bet Calculator - Four numbers
• Roulette Street Bet Calculator - Three numbers
• House Edge Calculator - Compare games

Conclusion

Split bets cover two adjacent numbers for a 17:1 payout—offering a middle ground between single-number risk and wider coverage. Our calculator shows exact probability and expected value for this versatile inside bet.

Calculate Split Bet Odds Now →

Placing that chip on the line between 17 and 18 covers both numbers at 5.41% combined probability. Our calculator confirms split bets carry the same 2.70% edge as every other European roulette wager—choose by preference, not false advantage.