Free · Android · 7 Systems · No Ads

Free blackjack card counting trainer
with live true count and edge feedback.

Counting Edge for Android

Train with Hi-Lo, KO, ReKO, and four advanced systems. Track the running count, convert to true count, estimate player edge, and size bets faster before you ever sit at a live table.

Download APK — Android Try the Live Demo
7
Seven systems built in Start with Hi-Lo, then move up to Level 2 and Wong Halves.
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Live edge and bet ramp See true count, estimated edge, and bet units react instantly.
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Private and friction-free No ads, no account, and core app usage stays on your device.

All 7 systems free forever. Open source (Apache 2.0) — source on GitHub. Current version: v1.0.0.

Hi-Lo
+7 Running
+2.5 True
+0.7% Edge
Bet Units
4
A-1
2+1
3+1
4+1
5+1
6+1
70
80
90
10K-1
Recent Cards
5 K A 3 7 2
📐
Built on proven mathThe same principles pros use to track player edge at the table
🃏
7 systems in one appFrom Hi-Lo and KO to Hi-Opt II, Omega II, Zen, and Wong Halves
📊
Live edge + bet sizingRunning count, true count, edge, and units update together in real time
🔒
No account. No ads.Every system free, open source, and no server needed
7 Counting
Systems
1–8 Deck
Configurations
10+ Table Rule
Options
1–12 Bet Unit
Ramp
0 Data
Collected
Live Demo

Try the Hi-Lo Card Counting Simulator — Right Now

Use this interactive card counting simulator to practice Hi-Lo on any shoe. Tap cards as they're dealt and watch your running count, true count conversion, blackjack edge, and bet spread recommendation update live — exactly like the app. Perfect for practising before you sit down at a real table.

See the count move in under 10 seconds

Pick a shoe, tap a few cards, and watch the running count, true count, and recommended bet react instantly.

1 Choose decks 2 Tap cards 3 Read the edge
Need the tag values? Practice drills
Start with a few low cards Low cards push the count up. High cards push it down. The app translates that into edge and bet guidance automatically.
Flat Bet
0 Running
0.0 True Count
-0.5% Est. Edge
Bet Recommendation
1
Total Decks
6.0
Recent Cards
Tap a card to start, or use the sample hand to see the count shift.
Ready for full-shoe practice? Use the same workflow in the app with all 7 systems, rule-aware charts, undo history, and table-rule presets.
Practice in the App
Hi-Lo Tag Values
2 · 3 · 4 · 5 · 6
Low cards — favour the player
+1
7 · 8 · 9
Neutral cards
0
10 · J · Q · K · A
High cards — favour the dealer
−1
Bet Ramp
True Count < 11 unit
True Count 1 – 22 units
True Count 2 – 34 units
True Count 3 – 48 units
True Count ≥ 412 units
How to read the count When high cards leave the deck, the remaining shoe is rich in low cards — which hurts the player. A positive count means more high cards remain, shifting the edge your way. The higher the true count, the bigger you bet.
Features

Everything You Need to Master Card Counting

A complete blackjack counter toolkit — from beginners learning Hi-Lo to advanced players refining Wong Halves index plays.

🃏

Live Count Tracking

Tap card ranks as they're dealt. Running count, true count, and deck penetration update instantly.

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Live Blackjack Edge Calculator

Real-time blackjack edge % driven by your true count, table rules, and deck configuration — calibrated from Wizard of Odds rule-variation data.

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Bet Spread & Recommendations

Configure your bet spread and let the app recommend the optimal unit size — a 1→2→4→8→12 unit ramp based on your live true count and counting system.

📋

Basic Strategy Charts with Count Deviations

Complete basic strategy for hard totals, soft totals, and pair splits — rule-aware and fully updated with count deviation cells marked ✱. See the chart →

⚙️

Table Rules Configuration

S17/H17, peek rules, 3:2/6:5 payouts, DAS, surrender, resplit aces, 6-card Charlie, and more.

↩️

History & Undo

Rolling panel of the last 15 cards. Undo any mis-tap without losing your place in the count.

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Ace Side Count & True Count Conversion

Automatic true count conversion from the running count — plus a dedicated ace side-count panel for Hi-Opt II and Omega II Level 2 precision.

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One-Screen Workflow

Count display, deck controls, card input, and bet ramp — all on a single scrollable screen.

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Completely Private

No account. No server. No analytics. Every byte stays on your device.

Training aid only. This app is for educational and practice purposes. It is not gambling advice, bankroll management advice, or a guarantee of any casino outcome.
Try the Live Simulator → Read the Card Counting Guide →
Counting Systems

Seven Blackjack Card Counting Systems, One App

Every major card counting system used in professional blackjack and 21 — from beginner Level 1 to advanced Level 3. Whether you start with Hi-Lo or go straight to Wong Halves, pick your level and move up as you improve. Compare all seven side by side →

Hi-Lo
Level 1 Balanced True Count

The world's most widely-used card counting system — proven by professionals for decades.

2–6+1 7–90 10–A−1
  • Most documented system — vast strategy tables and resources available
  • Excellent betting correlation (0.97) for a Level 1 system
  • Used by the MIT Blackjack Team and most professional counters
  • True count division required mid-hand
  • Aces not separately tracked without a side count

Best for: Beginners and experienced players alike — the standard starting point

Full Hi-Lo guide: values, bets and index plays →

KO (Knock-Out)
Level 1 Unbalanced

Skips true count conversion entirely — simpler and faster to use at a live table.

2–7+1 8–90 10–A−1
  • No true count conversion — just use the running count to bet
  • Easier to maintain accuracy under casino pressure
  • Nearly as powerful as Hi-Lo for single and double-deck games
  • Less accurate in multi-deck shoes without adjustment
  • Index plays require conversion, reducing mid-hand flexibility

Best for: Players who find true count division distracting at live tables

Full KO guide → · Hi-Lo vs KO →

ReKO
Level 1 Unbalanced

KO's simplicity with a calibrated starting count — accurate across every shoe size without converting to a true count.

2–7+1 8–90 10–A−1
  • Adjusted starting count eliminates KO's multi-deck accuracy problem
  • No true count conversion — same mental simplicity as KO
  • Works consistently from single-deck to 8-deck shoes
  • Must memorize the starting count for each shoe size
  • Still unbalanced — theoretically less precise than balanced systems

Best for: KO users who play at multiple venues with different deck counts

Hi-Opt II
Level 2 Balanced True Count

A powerful Level 2 upgrade with higher playing efficiency and a dedicated ace side-count panel in the app.

2,3,6,7+1 4,5+2 8,9,A0 10–K−2
  • Significantly higher playing efficiency than Hi-Lo — better index decisions
  • Ace side count (built into the app) dramatically boosts betting accuracy
  • Widely used by serious advantage players at multi-deck tables
  • ±2 tag values require more mental effort than Level 1 systems
  • Ace side count adds a second mental tracking layer

Best for: Experienced counters ready to invest in a meaningful edge increase

Full Hi-Opt II guide →

Omega II
Level 2 Balanced True Count

A precise Level 2 count with higher playing efficiency than Hi-Lo — sharper index plays, best with an ace side count.

2,3,7+1 4,5,6+2 8,A0 9−1 10–K−2
  • Higher playing efficiency than Hi-Lo — more accurate index plays and deviations
  • Ace side count available in-app for full precision
  • Developed by Bryce Carlson; used in professional play
  • The 9 = −1 tag is an unusual value that takes extra practice to internalize
  • Betting correlation (0.92) trails Hi-Lo's 0.97 unless you keep an ace side count

Best for: Experienced counters who want more accurate playing decisions than Hi-Lo gives

Zen Count
Level 2 Balanced True Count

A well-rounded Level 2 system that tracks aces natively — no separate side count needed.

2,3,7+1 4,5,6+2 8,90 A−1 10–K−2
  • Aces are tagged (−1) — no separate ace side count required
  • Strong balance of betting correlation and playing efficiency
  • One of the most versatile Level 2 systems for multi-deck play
  • The 5 = +2 and A = −1 tags take time to drill to automaticity
  • More complex than Hi-Lo — not ideal as a first system

Best for: Players who want Level 2 accuracy without the burden of an ace side count

Wong Halves
Level 3 Balanced True Count

The highest-precision counting system in existence — used by dedicated advantage players who demand every edge.

2,7+½ 3,4,6+1 5+1½ 80 9−½ 10–A−1
  • Highest betting correlation of any widely used system (0.99)
  • Fractional values capture deck composition changes that Level 1–2 systems miss
  • The benchmark system that serious advantage players graduate to
  • Half-point tags (½, 1½) are very difficult to maintain under casino pressure
  • Marginal gain over Level 2 unless you're consistently betting large spreads
  • Requires extensive practice before it's viable at a live table

Best for: Dedicated advantage players committed to maximizing every fraction of a percent

Full Wong Halves guide →

Not sure where to start? Read our guide to choosing the right system →

Quick Start

Up and Running in 30 Seconds

A simple top-to-bottom workflow for practising at home before you play a real shoe game.

1

Set Table Rules

Open Menu → Table Rules. Configure S17/H17, payout, DAS, surrender, and other options to match the table you're training for.

2

Choose a Counting System

Open Menu → Select Counting System. Start with Hi-Lo; move to Level 2 or 3 as you advance.

3

Configure the Shoe

Set Total Decks (1/2/4/6/8) and drag the Decks Remaining slider to reflect shoe depth.

4

Tap Cards as Dealt

Two rows of card buttons — A and 2–5 on top, 6–9 and 10-K below. Running and true counts update live.

5

Read Your Edge & Bet Size

The Bet Recommendation card shows your unit ramp position (1→2→4→8→12). Edge % shows your current advantage.

6

Consult the Strategy Chart

Tap Strategy Chart for a full rule-aware basic strategy table with deviation cells highlighted for the current count.

Pro Tips
🎯
Start simple. Hi-Lo at Level 1 is used by most professional counters — master it before moving up.
⚡
Use the cheat sheet. Menu → Show Cheat Sheet displays card tag values grouped by system for quick reference.
↩️
Missed a card? The Last 15 Cards panel and Undo button let you correct mistakes without resetting.
♠
6:5 tables cost you. Set the payout rule and watch the Edge % drop — a reminder to find better tables.
📐
Deviations matter. Strategy cells marked ✱ change at certain true counts — learn them for maximum edge.
Legends of the Felt

The People Who Beat the House

These aren't myths. Real people used real mathematics to win millions — and the system they used still works today.

1960s

Edward O. Thorp

The Father of Card Counting

Thorp proved that deck composition changes the player's edge and turned blackjack from folklore into a math problem players could actually solve.

📖 Beat the Dealer made counting teachable
1970s–1980s

Ken Uston

The Legal Pioneer

Uston helped push card counting into the mainstream and won a landmark New Jersey case confirming that counting cards is a legal mental skill.

⚖️ Helped establish the legal right to count cards
1980s–2000s

The MIT Blackjack Team

Bringing Down the House

MIT students and alumni proved these methods worked under real casino pressure, turning disciplined counting into one of gambling's most famous success stories.

🎬 Helped make team-based card counting globally famous
Read the full card-counting timeline
History

How Card Counting Was Born

From a 1953 academic paper to Hollywood — the story of how mathematicians turned the tables on the house.

1953

The First Mathematical Proof

Roger Baldwin, Wilbert Cantey, Herbert Maisel, and James McDermott — four US Army mathematicians — publish "The Optimum Strategy in Blackjack" in the Journal of the American Statistical Association. Using hand calculators, they produce the first mathematically correct basic strategy, proving the house edge can be minimised to under 0.5%.

1960

Thorp Cracks the Code

MIT mathematics instructor Edward O. Thorp uses an IBM 704 mainframe computer to discover that removing low cards from the deck shifts the odds in the player's favour. He presents "Fortune's Formula: A Winning Strategy for Blackjack" at the American Mathematical Society's annual meeting — the first proof that counting cards gives a genuine edge.

1962

Beat the Dealer Changes Everything

Thorp publishes Beat the Dealer, introducing the Ten-Count system to the public. The book becomes a New York Times bestseller. Panicked casinos briefly change rules to hamper counters — only to reverse them when business drops sharply. The cat-and-mouse game between counters and casinos begins in earnest.

1966

Hi-Lo Arrives

Thorp's revised second edition of Beat the Dealer presents the Hi-Lo counting system — simpler and more practical than the Ten-Count. Developed with Julian Braun of IBM, Hi-Lo becomes the world's most widely used counting system and remains so to this day.

1970s

The Big Player Team Concept

Al Francesco invents the team-play approach: low-betting spotters count down the shoe and signal a high-betting Big Player to sit in only when the count is deeply positive. The Big Player appears to be a casual, lucky gambler — and casinos have no idea what hit them. Francesco mentors a young Ken Uston, who takes the concept worldwide.

1975

Stanford Wong and Professional Blackjack

John Ferguson — writing under the pen name Stanford Wong — publishes Professional Blackjack, introducing the technique of back-counting: observing a table without betting and only joining mid-shoe when the count turns favourable. "Wonging" becomes standard practice among professional counters, and his Wong Halves system sets the precision benchmark for Level 3 counting.

1979–

Tommy Hyland's Enduring Team

Tommy Hyland forms a card counting team in 1979 that operates continuously for over four decades — the longest-running operation in the history of the game. Hyland's team successfully fights casino trespass charges in court on multiple occasions, setting important legal precedents that affirm the right to count cards in most jurisdictions.

1982

New Jersey Protects Card Counters

Barred from Resorts International in 1979, Ken Uston sues. In 1982 the New Jersey Supreme Court rules that Atlantic City casinos cannot bar players for counting cards. Casinos respond with more decks, earlier shuffles and rule changes that raise the house edge.

1980s–
2000s

The MIT Blackjack Team

Students and alumni from MIT — and later Harvard and other universities — form a series of teams that use Francesco's Big Player model with meticulous bankroll management and training. Operating across Las Vegas, Atlantic City, and international casinos, the teams win millions of dollars over two decades before increasing surveillance and shared casino databases make their faces too well-known.

2003

Bringing Down the House

Ben Mezrich's bestselling account of the MIT Blackjack Team brings card counting into mainstream culture. The 2008 film 21 — starring Kevin Spacey and Jim Sturgess — reaches a global audience of tens of millions, inspiring a new generation of aspiring counters and dramatically increasing interest in blackjack strategy.

Today

The Knowledge Is Yours

Facial recognition, RFID-tagged betting chips that log every wager, and shared counter databases make large-scale professional play harder than ever. But the mathematics hasn't changed — the edge is still there for anyone disciplined enough to learn it. The same systems that professionals used to win millions are now available to practice on your phone.

Start Training →
FAQ

Common Questions About Card Counting

How does card counting work in blackjack?
Card counting works by assigning a tag value to every card dealt. In the Hi-Lo system — the most popular for beginners — low cards (2–6) score +1, neutral cards (7–9) score 0, and high cards (10, J, Q, K, A) score −1. You add each tag to a running total as cards come out of the shoe. When the running count is high and positive, the remaining deck is rich in tens and aces, which favour the player. Dividing the running count by the number of decks remaining gives the true count — the precise betting signal used by professional counters. A true count of +2 or above typically signals a player edge over the house.
What is card counting in blackjack?
Card counting is a legal blackjack strategy that tracks the ratio of high to low cards remaining in the shoe. When the count is positive, the deck is rich in tens and aces — shifting the mathematical edge from the house to the player. Edward Thorp proved the system in 1962, and the MIT Blackjack Team later used it to win millions across Las Vegas and Atlantic City. The same principles apply to 21 card counting in any multi-deck format.
How does the Hi-Lo card counting system work?
In Hi-Lo, each card is assigned a tag: low cards (2–6) are +1, neutral cards (7–9) are 0, and high cards (10, J, Q, K, A) are −1. As cards are dealt you maintain a running count by adding each tag. Dividing the running count by the number of decks remaining gives the true count — your betting signal. A true count of +2 or higher indicates a player edge over the house. Try it in the interactive demo above.
Is card counting legal?
Yes — card counting is completely legal in most jurisdictions worldwide. It is a mental skill, not cheating. In 1982 the New Jersey Supreme Court ruled in Uston v. Resorts International that Atlantic City casinos cannot bar players for counting cards; casinos there responded with countermeasures such as more decks and earlier shuffles. Nevada casinos can refuse service and ask a counter to leave, but counting in your head is not a crime. This app is a training tool for understanding and practising the mathematics of blackjack.
Can I use Counting Edge to practice for online blackjack?
Mostly no. Standard online blackjack uses a random number generator that shuffles after every hand, so there is nothing to count. Live dealer tables deal from a real shoe, but many use continuous shufflers or reshuffle early, and when only half the shoe is dealt even a skilled counter has little or no edge. Counting Edge is built for practising the shoe games dealt in casinos.
What is blackjack edge and how does the app calculate it?
Blackjack edge is the percentage advantage held by either the player or the house. With perfect basic strategy on a standard 6-deck S17 game the house edge is roughly −0.46%. Card counting shifts this: each true count point adds approximately +0.5% to the player's edge. At true count +2, for example, the player holds a +0.54% advantage. The app calculates your live blackjack edge from your current true count combined with the exact table rules you've configured — S17/H17, 3:2 vs 6:5 payout, DAS, surrender, and more.
What is the difference between running count and true count in 21?
The running count is the raw cumulative total of card tags as they are dealt. The true count normalises this for the number of decks remaining: true count = running count ÷ decks remaining. In 21 card counting, the true count is the accurate signal for betting decisions — because a running count of +6 with 4 decks left is far weaker than the same count with 1 deck remaining.
Which card counting system should I start with?
Start with Hi-Lo. It is the most widely used card counting system among professional players and offers the best balance of simplicity and effectiveness. Once you can accurately maintain the Hi-Lo count under table pressure, consider moving to KO (no true count conversion needed) or advancing to Level 2 systems like Hi-Opt II or Omega II for more accurate playing decisions. Wong Halves — the highest-precision Level 3 system — uses fractional tag values and is suited to experienced counters only.
What is the house edge in blackjack and can card counting overcome it?
The house edge in blackjack is the mathematical advantage the casino holds over a player using perfect basic strategy. On a standard 6-deck S17 game it is approximately −0.46%. Card counting flips this: each true count point adds roughly +0.5% to the player's edge. At a true count of +1, the game is nearly break-even. At +2 or above, the player holds a genuine positive edge over the house. The app calculates your live edge based on your current true count and your exact table rules — including payout ratio, soft-17, and surrender options — so you can see the effect of each rule in real time.
Can casinos detect card counters?
Yes — modern casinos use a combination of facial recognition, RFID-tagged chips that record every bet, surveillance analytics, and shared counter databases (previously run by Griffin Investigations) to identify advantage players. Common countermeasures include shuffling mid-shoe, reducing deck penetration, limiting bet spreads, and asking suspected counters to leave. Card counting is not illegal, but casinos are private property and can bar players. This is why discretion — avoiding extreme bet spreads and table-hopping — is as important as the mathematics.
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Upcoming Features

Start training now, then join the beta if you want what's next.

Install v1.0.0 now from GitHub. If you want a heads-up on new features and systems before they land, join the waitlist too.

Early feature access
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Your Edge Awaits

The Math Works.
Start Training.

Thorp proved it. The MIT team lived it. Now it's free on your phone — no ads, no account, no catch.

Download APK — Android Try the interactive demo first →