Casino Korea

Blackjack Basic Strategy Checker

Blackjack is unique among casino games because player decisions directly affect the outcome. Unlike roulette or slots where every choice has the same expected value, blackjack offers mathematically optimal decisions that vary depending on your hand and the dealer's upcard. This tool helps you learn these optimal decisions—and understand why even perfect play cannot eliminate the house edge.

Basic strategy was developed through computer simulations of millions of hands, first published by mathematicians in the 1950s and refined by experts like Stanford Wong and Edward Thorp. Following basic strategy perfectly reduces the house edge to approximately 0.5%—the lowest of any casino table game—but cannot make the game profitable without card counting techniques that are banned at most casinos.

Check Any Hand

Select your two cards and the dealer's upcard to see the mathematically optimal decision.

Why this decision?

Practice Mode

Test your basic strategy knowledge. Random hands will be dealt—choose the correct action.

0
Correct
0
Total Hands
-
Accuracy
0
Current Streak

Your Hand

7♠
9♥

Total: 16

Dealer Shows

K♦

Explanation:

Complete Basic Strategy Chart

This chart shows the mathematically optimal decision for every possible hand combination in a standard 4-8 deck game where the dealer stands on soft 17. These strategies were derived through computer simulations of billions of hands, as documented by the Wizard of Odds, one of the most respected gambling mathematics resources.

Hit
Stand
Double Down
Split
Surrender

Hard Totals

Hand 2345678910A

Soft Totals (Hands with Ace counted as 11)

Hand 2345678910A

Pairs

Hand 2345678910A

Why Basic Strategy Cannot Beat the House

A critical misconception among gamblers is that learning basic strategy makes blackjack a "beatable" game. While basic strategy minimizes losses, it cannot eliminate the house edge. According to research published by the UNLV Center for Gaming Research, even perfect basic strategy play results in an expected loss of approximately 0.5% of all money wagered over time.

The Mathematics of Blackjack House Edge

The house edge in blackjack comes from several structural rules:

  • Player acts first: If you bust (exceed 21), you lose immediately—even if the dealer would also bust.
  • Blackjack pays 3:2 (not 2:1): A natural 21 should pay 2:1 based on true odds, but standard rules pay only 3:2.
  • Dealer follows fixed rules: The dealer must hit until 17, creating predictable patterns, but still benefits from the "player busts first" rule.

These rules create approximately 8% house advantage before player decisions. Basic strategy reduces this to ~0.5% through optimal decision-making, but cannot eliminate it entirely.

What About Card Counting?

Card counting can theoretically give skilled players an edge of 0.5-1.5% over the casino. However, this technique is explicitly banned at Kangwon Land and virtually all casinos worldwide. Casinos employ countermeasures including continuous shuffling machines, frequent deck changes, and banning suspected counters. In South Korea, any advantage play technique that violates casino rules could potentially be prosecuted under gambling fraud statutes, as detailed in our legal framework section.

The legality of card counting varies by jurisdiction. While not technically illegal in most places (it's using your brain, not a device), casinos reserve the right to ban players. As documented by the Wizard of Odds, casinos employ sophisticated countermeasures including continuous shuffling machines, multiple decks, and penetration limits that make sustained card counting nearly impossible in practice.

Expected Losses with Perfect Basic Strategy

Even with flawless basic strategy execution, you can calculate expected losses using our House Edge Calculator. For example:

This compares favorably to slots (typically 8-12% house edge) or American roulette (5.26%), but still represents a guaranteed long-term cost. Our Compound Loss Calculator can show how these losses accumulate over years and decades.

Common Strategy Mistakes

Many players make systematic errors that increase the house edge beyond the theoretical minimum:

Why This Tool Is Educational

This strategy checker serves purely educational purposes. Understanding optimal blackjack decisions demonstrates several important concepts about gambling mathematics:

  1. Decisions matter: Unlike pure chance games, blackjack rewards knowledge—but knowledge only minimizes, never eliminates, losses.
  2. Mathematics is precise: Every hand has a mathematically optimal decision derived from probability theory, not intuition.
  3. The house always wins: Despite optimal play, structural rules guarantee casino profitability over time.
  4. Skill has limits: Even perfect strategy execution cannot make gambling profitable.

For those concerned about gambling behavior, our Problem Gambling Self-Assessment Tool provides confidential screening based on validated research instruments.

Important Disclaimer

This tool is for educational purposes only. Learning basic strategy does not make gambling a wise financial decision. The house edge ensures casinos profit over time regardless of player skill. All forms of gambling risk financial loss. If you or someone you know has a gambling problem, visit our responsible gambling resources page or contact the National Council on Problem Gambling.

Related Tools and Resources

Continue exploring gambling mathematics with these related educational tools:

For comprehensive information about gambling in South Korea, including legal restrictions at Kangwon Land and enforcement of gambling laws, explore our complete collection of educational articles.