Blackjack Strategy Trainer 21 app icon

Blackjack Strategy Trainer 21

Master Basic Strategy, One Hand at a Time

Practice blackjack basic strategy with spaced repetition, instant feedback, and color-coded strategy charts. Train smarter, play better.

Get it on Google Play

Why Players Choose This Trainer

Spaced Repetition

The app targets your weak spots. Hands you get wrong appear more often until you master them, just like top language-learning apps.

Strategy Chart Viewer

Color-coded charts for Hard Totals, Soft Totals, and Pairs. See the correct play at a glance for your chosen rule set.

Three Rule Sets

Practice with S17 (Stand on Soft 17), H17 (Hit on Soft 17), or ENHC (European No Hole Card) rules.

Instant Feedback

See immediately whether your decision was correct. Wrong answers highlight the right play so you learn on the spot.

Daily Streaks & Goals

Stay consistent with daily goals that scale with your experience, plus streak tracking to keep you motivated.

Detailed Statistics

Track your accuracy across Hard Totals, Soft Totals, Pairs, and Surrender hands. Know exactly where to improve.

How It Works

  1. See a hand You're dealt a random blackjack hand with a dealer upcard, shown as realistic playing cards on a casino-green felt.
  2. Choose your action Tap Hit, Stand, Double, Split, Surrender, or Skip. Six actions, one tap.
  3. Get instant feedback The app tells you if you're right. If wrong, it shows the correct play and highlights the right button.
  4. Build muscle memory Spaced repetition focuses on your weak hands. Over time, correct plays become automatic.

Supported Rule Sets

S17

Dealer stands on soft 17. The most common rule in US casinos.

H17

Dealer hits on soft 17. Changes several key strategy decisions, especially for splitting.

ENHC

European No Hole Card. The dealer draws their second card after players act. Common in Europe and Asia.

Free Blackjack Strategy Guides

Seven in-depth guides covering basic strategy, rule variations, and the math behind every decision. No paywall, no signup.

Basic Strategy

The full chart and the reasoning behind every cell.

S17 vs H17

The soft 17 rule and the six cells it changes.

When to Double Down

Every doubling decision, with examples and the math.

When to Split

Pair splitting from A,A to 10,10 — and the 9,9 vs 7 trap.

When to Surrender

The four hands worth folding for half a bet.

House Edge

How each rule moves the math, from 0.15% to 2%.

How to Memorize

A realistic study plan using spaced repetition.

View all strategy guides →

Frequently Asked Questions

What is blackjack basic strategy?
Basic strategy is the mathematically optimal way to play every blackjack hand based on your cards and the dealer's upcard. It reduces the house edge to under 0.5% and is the foundation for all serious blackjack play.
Is this app free?
Yes. The app is free to download and use. It includes ads to support development. You can earn streak shields by watching optional rewarded ads.
Which rule set should I learn first?
Start with S17 (Stand on Soft 17) as it's the most common rule in US casinos. Once you've mastered it, you can practice H17 or ENHC for different casino environments.
How does spaced repetition work?
The app tracks your accuracy on each specific hand combination. Hands where your accuracy is below 80% (with at least 3 attempts) are served more frequently, so you practice what you need most.
Does this app teach card counting?
No. This app focuses purely on basic strategy — the foundation every blackjack player should master first. Each hand is generated independently without deck tracking.
Can I sync my progress across devices?
Yes. Create an account to sync your statistics and streak shields across devices via cloud backup.

Start Training Today

Free on Google Play. No sign-up required.

Download for Android