The Fabulous Four are four high-value surrender indexes used with card counting. They are not four counting systems and do not replace basic strategy. An index is usable only with the counting system, game rules and surrender procedure for which it was calculated.
What the name means
QFIT documentation describes the Fabulous Four as the top surrender indexes. It separately describes the Illustrious 18 as eighteen high-value playing indexes compiled by Don Schlesinger and the Sweet 16 as that set without the two ten-splitting decisions.
The groups serve different purposes. The Fabulous Four concern surrender decisions; the remaining index sets cover selected hit, stand, double, split or insurance departures.
Late surrender comes first
The usual application assumes late surrender is actually offered. With late surrender, the player gives up the hand and half the original wager only after the dealer has checked for blackjack when the procedure calls for a check. If the table does not offer the required form of surrender, the surrender index cannot be used.
Why a bare list can be misleading
Published index numbers can differ with the counting system, true-count convention, number of decks, dealer action on soft 17 and surrender rules. QFIT’s strategy documentation changes displayed tables when rule options change. For that reason, this page does not present one context-free list as universal.
How to use an index set
- Learn the correct basic strategy for the exact rules.
- Confirm that late surrender is offered and understand the dealer’s blackjack-check procedure.
- Use indexes published for the chosen count and true-count method.
- Keep the rule assumptions with every chart or simulator result.
- Test accuracy away from real-money play before relying on deviations.
What the indexes change in practice
Surrender decisions occur only in a narrow part of the game, so the value of these indexes depends on seeing the relevant hands while surrender is available. Their purpose is to preserve expected value in specific count situations, not to create a large or frequent win. A player can memorize all four and still lose a session because short-term card order dominates a small mathematical improvement.
Do not raise a wager merely because a surrender index is available. Betting decisions require a separate estimate of the remaining composition, an adequate bankroll and a risk limit. Track surrender errors separately from betting errors during practice so that a correct index decision does not hide poor stake control.
Why losing half can be the better decision
Consider a 20-dollar initial wager when valid late surrender is available. Surrender returns ten dollars and produces a net loss of ten dollars. To compare it with playing on, use the expected net result of the best available continuation, not simply the chance of losing the hand.
The following probabilities are invented for arithmetic practice. They do not describe a particular hand, true count or game. Assume the continuation can only win twenty dollars, push or lose twenty dollars, with no blackjack premium, additional wagers or fees.
| Example | Win / push / lose | Expected net result if played | Better modeled choice |
|---|---|---|---|
| A | 25% / 5% / 70% | −9 dollars | Continue: −9 exceeds −10 |
| B | 20% / 5% / 75% | −11 dollars | Surrender: −10 exceeds −11 |
For A, the calculation is 0.25 × 20 + 0.05 × 0 − 0.70 × 20 = −9 dollars. For B, it is 0.20 × 20 + 0.05 × 0 − 0.75 × 20 = −11 dollars. Both continuations lose more often than they win, yet surrender is preferable in only one of these examples. The point is to lose less in expectation, not to turn a weak hand into a profitable one.
Real strategy calculations must compare all legal alternatives under the actual rules, including additional stakes and their settlement where relevant. A surrender index summarizes a modeled crossover; you cannot derive it from these invented probabilities. Losing a played hand afterward does not prove that surrender would have been the better decision before the outcome was known.
Check eligibility before comparing the index
Confirm the decision is still available at this point in the hand. Ordinary late surrender is generally an initial two-card option; do not assume it remains available after a hit, split or double. Follow the actual rules if a variant allows something different. Early surrender, which can precede the dealer’s blackjack check, is a separate rule and needs separate strategy.
During practice, state the rule, classify the hand, confirm eligibility, calculate the count using the matching convention and then apply the appropriate surrender index. If surrender is unavailable, continue with the rule-matched hit, stand or other legal decision. Do not apply a surrender threshold as though it were a hit/stand threshold. The Illustrious 18 guide provides the related Hi-Lo reference and explains why pair and surrender decisions need to be resolved before reading a hard-total row.
Sources
Further reading
Strategy indexes can change a few decisions; they do not remove variance or guarantee a profit.
