Blackjack 21

Play blackjack. Learn the decisions. Train the count.

Blackjack 21 combines a clean, fully playable card game with practical tools for learning basic strategy and card counting. There are no ads and no account is required.

PLAY YOUR WAY

• Choose 1, 2, 4, 6, or 8 decks

• Set dealer soft 17, double after split, resplitting, late surrender, and shuffle depth

• Practice split, double, surrender, and insurance decisions

• Review hand history with every decision graded: what you played and what strategy recommends

• Track your performance and strategy accuracy

• Light and dark themes, plus a four-color deck for easier reading

• Made for iPhone and iPad

LEARN BASIC STRATEGY

• Use strategy charts matched to your selected rules

• Drill hard totals, soft totals, pairs, or mixed hands

• Focused practice saves the hands you miss and brings them back until you get them right three times in a row

• Get immediate feedback with concise probability-based explanations

• Your training progress is saved between sessions

• Learn eight card-counting systems (Hi-Lo, KO, Hi-Opt I and II, Omega II, Red 7, Zen Count, and Wong Halves) plus practical bankroll fundamentals

GO FURTHER WITH PRO

One optional lifetime Pro purchase unlocks:

• Live running and true counts for all eight systems, with Show, Hide, or Quiz me modes

• Strategy basis: play and grade by basic strategy or count-adjusted strategy, with index-deviation and insurance guidance

• Bet suggestions from preset or custom bet ramps

• Speed count, Deck countdown, Deviations, and Bet ramp drills

• Bankroll calculator

PRIVACY AND ACCESS

• No advertising or cross-app tracking

• No account or sign-in

• Core gameplay and training work offline

• Optional anonymous usage data helps us see which features are useful. It is on by default and you can turn it off anytime in Settings

• Optional bug reports and automatic crash diagnostics help us improve reliability

Blackjack 21 simulates casino card play for entertainment and training only. It does not offer real-money gambling, prizes, wagering, or cash-out.