Blackjack Card Counting Calculator
Calculate true count, player advantage, and optimal bet sizing
Formula:True Count = Running Count / Decks Remaining
Count Tracker
Enter your current count and deck status
HI LO Card Values
2
+1
3
+1
4
+1
5
+1
6
+1
7
0
8
0
9
0
10
-1
A
-1
High Count - Increase Bet!
True Count
+3.0
Player Edge
+1.00%
Running Count
+6
Optimal Bet
$75
Betting Ramp
TC ≤ 0
$25
TC +1
$25
TC +2
$50
TC +3
$100
TC +4
$200
TC +5+
$300
Counting Scenarios
Practice with different count situations
Quick Answer
Key concepts at a glance
Card counting works by tracking the ratio of high to low cards remaining. High cards (10-A) favor the player, low cards (2-6) favor the dealer. In Hi-Lo, add +1 for 2-6, 0 for 7-9, -1 for 10-A. A positive true count indicates player advantage. At +2 true count, the player has roughly a 1% edge. Bet more when the count is positive, less when negative.
Key Facts About Card Counting
Essential knowledge for counters
- Hi-Lo is the most popular system: +1 (2-6), 0 (7-9), -1 (10-A)
- Running count is the raw count; true count adjusts for decks remaining
- True count = Running count / Decks remaining
- Each +1 true count adds about 0.5% player advantage
- At +2 true count, player has roughly 0.5-1% edge over house
- Minimum 2:1 or 3:1 bet spread needed to profit from counting
- Card counting is legal but casinos can ban you for it
Frequently Asked Questions
Common questions about card counting
How does card counting work?
Card counting tracks the ratio of high cards (10, J, Q, K, A) to low cards (2-6) remaining in the deck. When more high cards remain, players have an advantage because: blackjacks are more likely, doubling down is more profitable, and the dealer busts more often. Counters bet more when the deck is "hot" (rich in high cards).
What is the difference between running count and true count?
Running count is the raw cumulative count from the start of the shoe. True count normalizes this for the number of decks remaining. With 6 decks and a running count of +12 after 3 decks dealt, true count = +12 / 3 = +4. True count better represents actual advantage and is used for betting decisions.
Is card counting illegal?
Card counting is not illegal - it is using your brain to play better. However, casinos are private property and can refuse service to anyone. They may "back off" counters (ask them to leave blackjack) or ban them entirely. Using devices to count is illegal.
Which counting system should I learn?
Start with Hi-Lo. It is the most popular, well-documented, and offers a good balance of power and simplicity. More complex systems like Wong Halves or Zen add marginal accuracy but are much harder to use under casino conditions. Master Hi-Lo before considering others.
How much can I make card counting?
Skilled counters with adequate bankroll can expect 0.5-1.5% edge over the house. At $25 average bet, 100 hands/hour, this is $12.50-$37.50/hour expected profit. However, variance is extreme - you can easily lose $5,000 in a session even with an edge. Most counters need $20,000+ bankroll.
How this works
Calculations follow the published mathematics of the game — combinatorics for cards, probability theory for dice, and expected-value accounting for wagers. Results are verified against independent references (primarily Wizard of Odds). No calculation here is an opinion or recommendation; it is arithmetic applied to the rules of the game.
What this tool can’t do
When to consult a professional
This tool computes probability and expected value. It is not a betting system and cannot predict the outcome of any individual wager. If gambling is causing problems for you or someone you know, call the National Problem Gambling Helpline at 1-800-GAMBLER.
Sources
- [1]Wizard of Odds — Michael Shackleford, ASAIndustrywizardofodds.comAccessed Apr 21, 2026
Actuary; widely cited casino-game probability reference. Used for house-edge and EV verification.
- [2]National Council on Problem GamblingOfficial sourcencpgambling.orgAccessed Apr 21, 2026
Responsible-gambling guidance and 1-800-GAMBLER helpline.
Joseph OrdunaFounder & Software Engineer
Full-stack software engineer specializing in embedded systems, web architecture, and AI/ML. Founder of Practical Web Tools. Built the gesture-controlled drone IP acquired by KD Interactive (Aura Drone, sold on Amazon).