In professional blackjack, the running count is a raw number — it tells you what cards have passed, but not the density of high cards remaining in the shoe. To gain a mathematical edge over the casino, you must convert that raw number into the True Count.
This calculator handles the division instantly. Enter your Hi-Lo running count, estimate the decks remaining, and see your true count with estimated player advantage. Use it to practice the critical skill of deck estimation before hitting the casino floor.
True Count Calc
Hi-LoHi-Lo Card Values (Quick Reference)
Before you can compute a true count, you need the running count. The Hi-Lo system assigns every card a value:
| Cards | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10/J/Q/K | A |
|---|---|---|---|---|---|---|---|---|---|---|
| Hi-Lo Value | +1 | +1 | +1 | +1 | +1 | 0 | 0 | 0 | −1 | −1 |
| Group | Low Cards (good for player when removed) | Neutral | High Cards (bad for player when removed) | |||||||
A positive running count means more low cards have been dealt — so the remaining shoe is richer in 10s and Aces. A negative count means the opposite. For a comprehensive overview of how to use these values in practice, see our Card Counting Guide.
How to Use the Calculator
- Enter Running Count (RC): The cumulative count based on cards dealt. Use the +/− buttons or type directly.
- Set Decks Remaining: Use the slider (0.5 precision). Estimate by looking at the discard tray — a standard deck is about 2 cm (¾ inch) thick. Subtract discards from starting decks.
- Read the Output: The True Count (RC ÷ Decks Remaining) appears on the display. Below it, the Estimated Player Edge shows whether you have a positive expectation. Green = player advantage, Red = house advantage.
The edge estimate uses the standard Hi-Lo approximation: base house edge of −0.5% plus 0.5% per TC point. Your actual base edge depends on table rules — use the House Edge Calculator to find the exact number for your game, then add 0.5% per TC.
Player Edge by True Count
The table below shows the approximate player advantage at each true count, assuming a standard 6-deck game with ~0.50% base house edge:
| True Count | −2 | −1 | 0 | +1 | +2 | +3 | +4 | +5 |
|---|---|---|---|---|---|---|---|---|
| Player Edge | −1.50% | −1.00% | −0.50% | 0.00% | +0.50% | +1.00% | +1.50% | +2.00% |
| Action | Min bet | Min bet | Min bet | 2 units | 4 units | 8 units | 12 units | 12 units |
The “Action” row shows a common 1-12 bet spread for 6-deck games. The exact spread depends on your bankroll and risk tolerance. A wider spread (1-16 or 1-20) captures more edge but creates larger swings — use the Variance Calculator to model the tradeoff.
Real-World Examples
Example 1: The “False” Positive
Playing a 6-deck shoe, 1 deck dealt. Running Count: +10. This feels huge — but 5 decks remain. TC = 10 ÷ 5 = +2. You have a small edge (~0.50%), but this is not the time to push max bet. A beginner who bets based on the raw RC of +10 would be massively overbetting.
Example 2: The End-of-Shoe Sniper
Deep into the shoe, only 1 deck remaining. Running Count: +6. TC = 6 ÷ 1 = +6. This is a massive advantage (~+2.50%). Max bet. The lower RC is actually far more powerful because fewer decks remain — the high cards are concentrated. This is why penetration matters: deeper cuts create more opportunities for high TC counts.
Example 3: The Negative Count
Three decks into a 6-deck shoe. Running Count: −6. TC = −6 ÷ 3 = −2. Player edge: −1.50%. The shoe is depleted of 10s and Aces. You should be at minimum bet. Some counters leave the table at sustained TC −2 or below (“Wonging out”) to avoid grinding through a bad shoe.
True Count and Play Deviations
The true count does not only control bet sizing — it also changes basic strategy at specific thresholds. These changes are called “play deviations” or the “Illustrious 18.” The most important ones:
Insurance: Take insurance at TC ≥ +3 (normally never taken in basic strategy). At TC +3, there are enough 10-value cards remaining that the insurance bet becomes +EV.
16 vs 10: Stand at TC ≥ 0 (basic strategy says hit). The extra 10s in the shoe make hitting riskier and increase the chance the dealer busts on a subsequent card.
15 vs 10: Stand at TC ≥ +4. Similar logic, but you need a higher density of 10s to justify standing on 15.
For the full list of index plays, see the Deviations Calculator, which shows exactly which plays change at each TC threshold.
Related Blackjack Tools
- Card Counting Guide — Complete Hi-Lo system walkthrough
- Deviations Calculator — Index plays (the Illustrious 18)
- Penetration Calculator — How cut card depth affects counting EV
- House Edge Calculator — Find your base house edge to calibrate the TC edge model
- Bankroll Calculator — Risk of Ruin based on edge and bet spread
- Variance Calculator — SD per hand and N0 for counters
- Decision EV Calculator — Exact EV for Hit/Stand/Double/Split
- Basic Strategy Calculator — Optimal play before deviations