Blackjack Betting Unit Calculator

Calculate your optimal betting unit based on bankroll size, risk tolerance, and playing style for proper blackjack bankroll management.

Formula:Unit = min(Bankroll × Risk%, Bankroll ÷ UnitsNeeded)

Recommended Unit

$100

Range: $80-$120

Max Bet

$100

1x spread

Effective Units

100

Need 100 for 13% RoR

Bankroll & Risk Settings

$

Money dedicated to blackjack

% of bankroll per unit

Playing Style

Determines required unit count

%

Your advantage (negative = house edge)

Kelly Criterion Analysis

Full Kelly
$43
Half Kelly (Safer)
$22

Half Kelly is recommended to reduce variance while maintaining growth

Bankroll Analysis

100
Effective Units
100
Units Needed
~13%
Risk of Ruin
±$1,150
Hourly Std Dev

Quick Answer

With a $10,000 bankroll, optimal betting unit is $100-$200 (1-2% of bankroll). For card counters, the unit should support spreading 1-12 units. Conservative players use 1%, aggressive 2-3%. Kelly Criterion suggests betting edge/variance of bankroll.

Key Facts

  • ✓Standard recommendation: 1-2% of total bankroll per betting unit
  • ✓Card counters need 200-400 units for 1-12 spread
  • ✓Kelly Criterion: Bet = (edge × bankroll) / variance
  • ✓$5,000 bankroll = $25-$100 optimal unit
  • ✓Higher edge = larger optimal bet size
  • ✓Risk of ruin decreases with smaller bet sizing

Frequently Asked Questions

What is a betting unit in blackjack?

A betting unit is your standard bet size, typically 1-2% of your total bankroll. If you have $5,000, your unit would be $50-$100. Card counters use units to scale their bets based on the count while maintaining proper bankroll management.

How do I calculate my optimal betting unit?

Divide your total bankroll by the number of units you need. For basic strategy players, 50-100 units is sufficient. Card counters spreading 1-12 need 200-400 units minimum. $10,000 ÷ 200 units = $50 unit size.

What is the Kelly Criterion for blackjack?

The Kelly Criterion calculates optimal bet size as (edge × bankroll) / variance. For blackjack with ~1% edge, Kelly suggests betting about 0.8% of bankroll. Most advantage players use "half Kelly" or "quarter Kelly" to reduce variance.

How many betting units do I need for card counting?

For a 1-12 bet spread, you need 200-400 units to have less than 5% risk of ruin. With $10,000 bankroll and $25 units, you have 400 units - very safe. With $50 units, you have 200 units - adequate but more volatile.