A true count scales a running count by the amount of undealt cards under a specified counting system. It is not another running count and does not imply a fixed advantage percentage. Use the divisor, resolution and rounding method published for the chosen strategy.
Basic conversion
For a system that uses full decks remaining, the common form is:
true count = running count ÷ estimated decks remaining
If the running count is +6 and 1.5 decks remain, the unrounded true count is +4. The +4 result is a true count; calling it a running count changes the meaning.
Conversion conventions vary
QFIT documentation notes that most counts use full decks remaining, some use half-deck or quarter-deck units, and some unbalanced systems use no true-count adjustment. Truncation, flooring, rounding and resolution must match the strategy’s index tables.
Deck estimation
In a multi-deck game, the player estimates how much of the shoe remains, not merely how many cards have appeared. Estimation error changes the divisor and can move a result across an index or betting threshold.
Check the units before interpreting the number
Estimation resolution and divisor units are different choices. You may estimate remaining cards to the nearest half deck while still dividing by full decks remaining. In that case, 1.5 decks is the divisor 1.5, not 3 because it contains three half decks. A system expressly using half-deck units needs the matching indices; changing the denominator without changing the convention makes the result incompatible.
A small estimate error changes the answer
Take running count +5 with two decks actually remaining. The unrounded true count is +2.5. If you underestimate the remainder as 1.5 decks, you calculate about +3.33; if you overestimate it as 2.5 decks, you calculate +2. The running count can be correct while the denominator pushes the result across a decision boundary. Whether a particular index changes the action also depends on its published rounding rule.
Practise with measurable stacks and record actual remaining decks, your estimate, running count and the converted result separately. Include negative counts: an underestimated remainder exaggerates the magnitude in both directions. Do not treat uncertainty as evidence of a larger player advantage.
Negative counts expose rounding mistakes
For a quotient of −1.8, truncation toward zero gives −1, flooring toward negative infinity gives −2, and rounding to the nearest integer gives −2. These conventions are not interchangeable. At exact halfway values, follow the documented tie rule as well. Use the counting trainer to isolate deck estimation and conversion before adding strategy decisions. Its displayed result is a practice aid; it does not replace the chosen system’s instructions or establish a safe bet.
No universal edge per count
A rule such as “each true count adds 0.5%” is not universal. Expected value at a given count depends on rules, penetration, composition, strategy, index set and calculation method. Use a rule-matched simulation rather than a generic percentage.
Sources
Further reading
Keep the running count, remaining-card estimate and conversion convention in the same units.
Keep one true-count convention from practice to play
A true count is useful only when the deck estimate, division method and rounding rule match the index set you use. Decide whether remaining decks are estimated in full, half or quarter decks, and whether results are floored, truncated or rounded. Apply that method to both drills and real decisions.
For example, a running count of +7 with 2.5 decks remaining equals +2.8 before rounding. One index chart may treat that as +2 while another records +3. Write the convention beside the chart and test borderline examples. Consistency prevents a correct running count from producing the wrong deviation at the table.
