How we check the numbers

Every house edge, probability and average on this site comes from our exact calculation for the rules named next to it, not from typing. Payouts, phone numbers and laws are copied from their sources, which we name.

The engine

• For every rule set, the engine works out exactly how the dealer's hand finishes for each up card, from the cards left in the shoe.
• For every two-card hand it works out the average result of hitting, standing, doubling, splitting and surrendering.
• The strategy chart picks the move with the best average for each hand total, the same way published charts are built.
• Two simplifications are stated wherever they matter: split hands are treated as independent, and re-splits (up to 4 hands; aces once) are approximated.

The cross-check

A separate simulator, written without access to the engine, dealt billions of rounds with the engine's charts. Its results match the engine's house edge within the simulator's margin of error for every rule set tested.

Help lines

Phone numbers, opening hours and age limits on the responsible gambling page are copied word for word from the service's or regulator's own website. Each copy is stored with the date it was read, and the site will not build if a check is older than 100 days.

What we do not do

• We do not copy other sites' charts or tables.
• We do not publish casino ratings.
• We do not use photos taken from the internet. Illustrations are drawn for this site.