Flat Betting Calculator: The Mathematically Sound Approach

Flat betting—wagering the same amount on every bet—is the mathematically optimal approach for games with a house edge. No progression, no chasing, just consistent stakes. Our calculator reveals why simplicity beats complexity when the odds are against you.

What Is Flat Betting?

Flat betting means wagering the same fixed amount on every bet, regardless of previous wins or losses. No increasing after losses (Martingale), no decreasing after wins. Just consistent, predictable stakes that make bankroll management straightforward.

Quick Answer: Flat betting = same bet every time. $10, $10, $10... Win or lose. No progression. No chasing. Expected loss = (total wagered) × (house edge). Most predictable variance. Longest average session. No system can beat house edge, so why add complexity? Optimal for negative-EV games.

How to Use Our Calculator

Use the Flat Betting Calculator →

Calculate expected outcomes for flat betting.

Step-by-Step Instructions

1. Enter Bet Size: Fixed wager amount

2. Enter Number of Bets: Session length

3. Select Game: House edge applied

4. View Expected Loss: Mathematical outcome

5. See Variance Range: Possible results

Input Fields Explained

Field	Description	Example
Bet Size	Fixed wager	$25
Number of Bets	Total bets	100
Total Wagered	Action	$2,500
House Edge	Game edge	2.70%
Expected Loss	Math outcome	$67.50
Std Dev	Variance	±$250

Why Flat Betting Is Optimal

The Mathematical Truth

For negative-EV games:

No system changes expected value
All systems = (wagered) × (edge)

Flat betting:
$10 × 100 bets × 2.7% = $27 expected loss

Martingale:
Average $10 × 100 bets × 2.7% = $27 expected loss

Same math, different experience

Variance Advantage

Flat betting variance:

Predictable swings
Known worst case (bankroll size)
Consistent session length

Progression variance:
Wild swings
Catastrophic worst case
Unpredictable session length

Bankroll Efficiency

$200 bankroll, $10 flat betting:

Guaranteed 20+ bets (if unlucky)
Average 50+ bets (typical)
Could play 200+ bets (if lucky)

$200 bankroll, Martingale:
Could bust in 7 losses ($10→$640)
Average shorter sessions
Higher bust probability

Flat Betting vs Systems

Expected Value Comparison

All betting strategies:

Flat betting EV: -2.70%
Martingale EV: -2.70%
Fibonacci EV: -2.70%
D'Alembert EV: -2.70%
Paroli EV: -2.70%
Labouchère EV: -2.70%

Identical expected value
Systems can't change math

Risk Comparison

Risk of complete ruin:

Flat betting: Gradual depletion
Martingale: Sudden catastrophic
Fibonacci: Moderate escalation
D'Alembert: Gradual escalation

Flat = most predictable risk
No surprise wipeouts

Entertainment Value

What systems provide:

Excitement from progression
"Almost recovered" drama
Winning streak rushes

What flat betting provides:
Predictable session length
Lower stress
Clearer thinking
Focus on the game

Expected Value Analysis

Standard Calculations

Flat betting math:

Total wagered = Bet × Number of bets
Expected loss = Total × House edge

Example (European roulette):
$25 × 100 bets = $2,500 wagered
$2,500 × 2.70% = $67.50 expected loss

Simple, transparent math

Variance Understanding

Standard deviation:

For even-money bets:
SD = bet × √(number of bets)
$25 × √100 = $250

95% of sessions fall within:
Expected ± 2 × SD
-$67.50 ± $500
Range: -$567.50 to +$432.50

Session Outcomes

Probability of winning session:

Flat betting on roulette:
100 bets, $25 each

Win probability: ~45%
Lose probability: ~55%

Worse than 50-50 due to edge
But known, quantifiable

Real-World Examples

Example 1: Roulette Session

Standard evening:

$25 flat betting, 100 spins
European roulette (2.70%)

Expected loss: $67.50
Actual: Varies by luck

Won $150: Great session
Lost $200: Bad luck but within range
Lost $500: Very unlucky (but possible)

Example 2: Blackjack Session

Card player:

$50 flat betting, 100 hands
Basic strategy (0.50%)

Expected loss: $25
Much lower edge = less loss

Same bet size, lower cost
Game selection matters

Example 3: Craps Session

Pass line player:

$10 flat betting, 200 rolls
Pass line (1.41%)

Total wagered: $2,000
Expected loss: $28.20

Very low cost entertainment
Flat betting maximizes time

Example 4: Long-Term Reality

Regular player, one year:

$25 flat, 100 bets/session
50 sessions per year
Roulette (2.70%)

Total wagered: $125,000
Expected loss: $3,375

Actual varies but trends to expected
Flat betting = predictable budget

Bankroll Management

Sizing Your Bet

Conservative approach:

Bankroll ÷ 50 = bet size
$1,000 ÷ 50 = $20 per bet

Ensures long session
Survives bad variance
Consistent experience

Session Planning

Plan your session:

How many bets do you want?
What's your hourly budget?
When will you stop?

Flat betting makes this easy
Known cost per hour
Predictable depletion

Loss Limits

Setting limits:

Daily loss limit: 20 bets
If down 20 units, stop

Easy to track with flat betting
No surprise large losses
Clear stopping point

Common Mistakes

1. Thinking Flat Is Boring

Mistake: "Systems are more exciting" Problem: Excitement = variance = stress Fix: Focus on the game, not the system

2. Varying Bets Emotionally

Mistake: Betting more when "feeling it" Problem: Feelings don't predict outcomes Fix: Stick to flat regardless of hunches

3. Wrong Bet Sizing

Mistake: $100 bets with $300 bankroll Problem: Too few bets before potential bust Fix: 1-2% of bankroll per bet

4. Expecting Different Results

Mistake: "Systems must be better" Problem: Math doesn't change Fix: Accept flat is mathematically optimal

Frequently Asked Questions

Is flat betting really optimal?

For negative-EV games, yes. No system can change expected value. Flat betting minimizes variance and maximizes predictability.

Why do people use systems then?

Entertainment, excitement, the illusion of control. Systems feel more engaging but don't improve mathematical outcomes.

How much should I bet?

1-2% of your session bankroll. This ensures enough bets for an enjoyable session and survives normal variance.

Does flat betting guarantee I won't lose?

No. You'll still lose on average (house edge). But losses are predictable and never catastrophic.

Can I flat bet and still win?

In the short term, absolutely. Variance means you'll have winning sessions. Long-term, house edge prevails.

Is card counting flat betting?

Card counters vary bets based on count. That's different—they have a mathematical edge. For negative-EV games, flat is optimal.

Pro Tips

• Same bet every time: No exceptions

• 1-2% of bankroll: Proper sizing

• Game selection matters: Lower edge = less loss

• Predictable sessions: Budget accurately

• No chasing needed: Losses are expected

Related Calculators

• Martingale Calculator - Compare to progression
• Expected Value Calculator - Understand EV
• House Edge Calculator - Compare games
• Bankroll Calculator - Size your bets
• Roulette Odds Calculator - Game analysis

Conclusion

Flat betting isn't exciting—it's mathematically optimal. Our calculator shows expected loss, variance ranges, and why betting the same amount every time gives you the longest sessions, most predictable outcomes, and lowest stress. No system beats the house edge, so why add unnecessary complexity?

Calculate Flat Betting Outcomes Now →

Bet $25, every time, no exceptions. Our calculator proves that simplicity is the smartest approach when playing games with a house edge—and shows exactly what that straightforward strategy will cost you.