Spreadsheet Blackjack is a free unblocked blackjack game that runs entirely in your browser — no download, registration, or install required. The interface is disguised as a spreadsheet grid, making it discreet enough for a quick round at the office or school. Behind the familiar rows and columns lies a full-featured blackjack simulator with configurable rules, a card counting trainer, and keyboard shortcuts.
Use the built-in card counting trainer to practice Hi-Lo, KO, Omega II, Hi-Opt I & II, Wong Halves, or Red 7 in real time. Adjust the number of decks, toggle splitting and doubling rules, or enable Double Down Madness for a higher-stakes challenge. A boss key (press H) hides the game instantly behind an innocent spreadsheet — and the game auto-hides itself when you switch tabs or windows, with a disguised browser tab title to match. Keyboard betting shortcuts (J/K for step up/down, U/M for min/max) let you play without touching the mouse.
Yes. Spreadsheet Blackjack is completely free to play. There are no ads, microtransactions, or hidden fees. The entire game runs client-side in your browser — no downloads and no accounts required.
Yes. The game includes a card counting trainer that supports Hi-Lo, KO, Omega II, Hi-Opt I, Hi-Opt II, Wong Halves, and Red 7. The running count and true count are displayed directly in the grid, so you can verify your mental count with every hand — useful for both beginners learning the system and experienced players staying sharp.
Configure bankroll size, min/max bets, number of decks (1–12), splitting, doubling, double after split (DAS), max split hands, re-splitting aces, ace-split-one-card-only, and Double Down Madness mode. Every rule change takes effect immediately on the next round.
Press H at any time to hide the game behind a normal-looking spreadsheet. All game state is preserved — press H again to resume exactly where you left off. The game also hides itself automatically when you switch browser tabs or windows, and while hidden the tab title changes to an innocent-looking file name, so an over-the-shoulder glance shows only a spreadsheet.
That is what the game is built for. It looks like a spreadsheet, so a glance from your boss shows only a grid of numbers. The boss key (press H) hides it instantly, it auto-hides when you switch tabs, and the browser tab title is disguised while hidden. Your bankroll and session are saved locally, so you can close the tab and pick the game up on your next break. No download or account is needed, so nothing appears in your installed apps.