Card Counting Blog
Expert guides, strategies, and training tips from the Protocol 21 team. Everything you need to master card counting and beat the house.
Featured Guides
Hi-Lo Card Counting System: Complete Guide for Beginners
Master the Hi-Lo card counting system with our comprehensive guide. Perfect for beginners looking to learn the most popular counting method.
The Ultimate Guide to Blackjack Card Counting Apps (2026 Edition)
The definitive guide to choosing the best card counting app. We review the top trainers, simulators, and free tools to help you beat the house.
All Articles
How Does Card Counting Work in Blackjack?
Learn the fundamentals of card counting in blackjack. Understand how advantage players track cards to gain an edge over the casino.
Read ArticleBest Card Counting Apps for Practice in 2026
Discover the top card counting trainer apps for iOS and Android. Compare features and find the best app to sharpen your blackjack skills.
Read ArticleHi-Lo Card Counting App | Protocol 21 Blackjack Trainer
Master the famous Hi-Lo card counting system. Protocol 21 provides the specific +1/-1 drills you need to learn Hi-Lo for iOS and Android.
Read ArticleKO (Knock-Out) Blackjack System App & Trainer
Learn the Knock-Out (KO) system without the math. Protocol 21 is the best app for unbalanced counting systems on mobile.
Read ArticleOmega II Card Counting Trainer | Advanced Blackjack App
Practice the complex Omega II system with Protocol 21. Our advanced mode supports Level 2 values and Ace side-counts.
Read ArticleZen Count Blackjack Trainer App
The Zen Count requires precision. Use Protocol 21's custom drills to master this powerful Level 2 balanced system.
Read ArticleRed 7 Card Counting App | Learn Unbalanced Counting
Learn Arnold Snyder's Red 7 system. Protocol 21 helps you practice the color-dependent starting counts unique to this system.
Read ArticleWong Halves Blackjack Trainer | Expert Counting App
Wong Halves is the hardest system to master. Protocol 21 is the only app that supports fractional values for expert drills.
Read ArticleBlackjack True Count Trainer App
Master mental math with Protocol 21. Learn to divide the running count by decks remaining instantly.
Read ArticleDeck Penetration & Estimation Drills
Improve your visual accuracy. Learn to guess how many decks are in the discard tray with precision.
Read ArticleCard Counting Speed Simulator
Increase your reaction time. Don't lose the count when the dealer speeds up.
Read ArticleReady to Practice What You've Learned?
Download Protocol 21 and start training with casino-grade drills.