Free on Android and iOS

Blackjack Strategy Trainer 21

The House Has a System. Do You?

Practice blackjack basic strategy one hand at a time. The app grades every decision against the chart, and the hands you get wrong appear more often until you master them. It covers S17, H17 and European no-hole-card rules.

Blackjack Strategy Trainer mobile application screen mockup running on high quality casino table

Why Players Choose This Trainer

Everything below is in the free app, on Android and iOS.

Your Mistakes Come Back

The app records how you play each hand. The hands you get wrong appear more often until you master them. Every decision is graded against the chart for the rule set you pick.

Full Interactive Charts

Color-coded charts of hard totals, soft totals and pairs for the rule set you pick. Open them any time in the app.

3 Rule Sets Supported

Train for the table you play: S17, H17 or European no-hole-card (ENHC) rules. The chart and the grading change with the rule set.

Instant Feedback

Each answer is graded right away. When you get a hand wrong, the app shows the correct move.

Streaks & Daily Goals

The daily goal is 10 hands. It rises to 25 after your first 100 hands, and to 50 after 500. Your streak counts the days in a row you play, and a Streak Shield keeps it alive when you miss a day. You earn a shield by watching an optional short video, and one when you create an account.

Accuracy by Hand Type

Your accuracy on hard totals, soft totals, pairs and surrender, each on its own, so you can see which kind of hand you miss most.

How It Works

Four steps, repeated for every hand. Played without mistakes, basic strategy cuts the house edge to about 0.5% in a six-deck game.

01

See the Hand

The app deals you two cards from a shuffled deck and shows the dealer's up card.

02

Choose Your Action

Tap Hit, Stand, Double, Split, Surrender, or Skip. Six buttons, one tap per hand.

03

Get Instant Feedback

A correct answer is marked at once. A wrong answer shows you the correct move.

04

Build Reflexes

The hands you get wrong appear more often until you master them.

Three Rule Sets

A few plays change with the table rules. Pick the rule set of your table, and the chart and the grading follow it.

S17 Rule Set

The dealer must Stand on Soft 17. This is the most common rule configuration across tables in standard US physical casinos.

H17 Rule Set

The dealer must Hit on Soft 17. Six plays change from S17: three doubles and three surrenders.

ENHC Rule Set

European No Hole Card. The dealer takes a second card only after all players act. Common at European tables.

Free In-Depth Strategy Guides

Learn the comprehensive math behind every decision. Core guides plus targeted answers for the rule and split questions players search most.

Basic Strategy

The core blackjack chart, explained cell-by-cell with mathematical logic.

Read Guide

Strategy Trainer

How to practice hard totals, soft totals, pairs and surrender against the chart for your rule set.

Read Guide

S17 vs H17

Understand the dealer's Soft 17 rules and the six strategic adjustments they demand.

Read Guide

When to Double

Every hard and soft double, the rules that change them, and the common mistakes.

Read Guide

When to Split Pairs

Learn when to split pairs from Aces to Tens, and how to avoid critical traps like 9,9 vs 7.

Read Guide

Split Rules

What counts as a pair, how resplits and split aces work, and which table rules change the split chart.

Read Guide

Soft 17

What soft 17 means, why H17 costs more, and how to tell which rule a blackjack table uses.

Read Guide

When to Surrender

Protect your bankroll. The four specific hands mathematically worth folding for half-bet recovery.

Read Guide

The House Edge

A deep dive into the casino mathematical benefit, showing how rules swing odds from 0.15% to 2%.

Read Guide

How to Memorize Fast

A concrete, realistic study framework utilizing spaced repetition schedules to lock in memory.

Read Guide

Explore Entire Strategy Repository

Frequently Asked Questions

Everything you need to know about Blackjack strategy training and app capabilities.

What is blackjack basic strategy?
Basic strategy is the best play for each of your hands against each dealer up card, worked out by computer for a given set of table rules. Played without mistakes, it cuts the house edge to about 0.5% in a six-deck game. The house still keeps that small edge.
Is this app free?
Yes. Blackjack Strategy Trainer 21 is free to download and use, and it shows ads. You can watch an optional short video to earn a Streak Shield.
Which rule set should I learn first?
The rule set of the table you play. If you do not know it, start with S17, where the dealer stands on soft 17. H17 changes six plays from S17, so it is quick to add once you know S17.
Which hands does the app show more often?
The app records how you play each hand. The hands you get wrong appear more often until you master them.
Does this app teach card counting?
No. The app teaches basic strategy, which card counters learn first. It deals every hand from a freshly shuffled deck, so there is no count to keep.
Can I sync my progress across devices?
Yes. Create a free account in the app. Your streak, stats, Streak Shields and lessons are then saved to the account, and you get them back on any device where you sign in.

Unleash Flawless Mathematical Play

Download Blackjack Strategy Trainer 21 today. Build unbreakable muscle memory, master hard margins, and confidently take your seat at any casino table.