Learn the reason behind the move
When to split pairs
Use the pair, dealer upcard and table rules together. Splitting creates separate hands and requires an additional stake.
Two hands replace one
An eligible starting pair can be separated, with an additional bet supporting the new hand. Further cards are dealt according to the table rules. Limits on resplitting and split aces vary. The supplied tool evaluates the first decision; it does not manage a betting round.
Blackjack rules and actions ↗Why 8,8 is different from hard 16
A pair of eights has a split option that a ten and six do not. In the default S17, no-surrender rules, split eights against every upcard. For H17 with late surrender, the supplied chart changes 8,8 against an ace to surrender, with split as the fallback.
Multi-deck strategy analysis ↗Tens and fives are separate cases
The reference keeps a pair of tens as 20. A pair of fives is evaluated as hard 10 instead of split. Do not assume that every pair should become two hands. Rank and upcard matter.
The DAS setting changes some pairs
With DAS enabled, 4,4 splits against 5 or 6 in this reference. Without DAS, those cells are hit. This is one reason the rule label must travel with a saved or printed chart. Changes are not merely cosmetic.
