Blackjack
Blackjack is the only commonly-offered casino game where mathematically perfect play brings the house edge under 1%. Played correctly against standard rules (6 decks, dealer stands on soft 17, double after split allowed), the house edge sits around 0.5%. Played incorrectly — by hunch, by superstition, by the dealer's tells — the same game runs at 2–3%. The gap between optimal and typical play is the single most-recoverable edge in any casino on the floor.
How to play blackjack
- 1You and the dealer each receive two cards. Yours are face up; the dealer shows one (the "up card") and hides one (the "hole card").
- 2Card values: 2-10 are face value, J/Q/K count as 10, Ace counts as 1 OR 11 (your choice, picked to your benefit).
- 3You aim to total higher than the dealer without going over 21. Going over 21 is a "bust" — you lose immediately, regardless of dealer outcome.
- 4On your turn you choose: HIT (take another card), STAND (stop), DOUBLE (double your bet, take exactly one more card), SPLIT (only if first two cards are a pair: split into two hands), or SURRENDER (give up half your bet on the spot — only some tables allow this).
- 5Once everyone stands or busts, the dealer reveals the hole card and hits until reaching 17 or higher (rules vary on whether dealer hits or stands on a "soft 17" — A6).
- 6Closest to 21 without busting wins. A "blackjack" (A + 10-value as your first two cards) typically pays 3:2 (some tables only pay 6:5 — never play 6:5).
What the numbers actually say
| House edge — perfect basic strategy, 6 deck S17 See /games/blackjack/strategy for the full chart | ~0.50% |
| House edge — perfect basic strategy, 6 deck H17 Dealer hits soft 17 → worse for you by ~0.15% | ~0.65% |
| House edge — typical play (no chart) Five times worse — purely from suboptimal decisions | ~2.5% |
| House edge — 6:5 blackjack tables Avoid 6:5 — costs ~1.4% extra by itself | ~2.0%+ |
| Probability dealer busts (vs your 12+) Higher (35%+) when dealer shows 4–6, lower (~21%) when dealer shows 7+ | ~28% on average |
| Probability you bust if you hit on 12 Why "stand on 12 vs dealer 4-6" works | ~31% |
The rules that actually matter
Always use a basic strategy chart
Why · Memorized basic strategy is the single biggest EV improvement available in any casino. Five-times-worse house edge without it.
Never take insurance
Why · Insurance is a separate side bet against dealer blackjack. Mathematical EV: −7.7%. Worst bet on the table.
Never play 6:5 blackjack
Why · A blackjack pays 6:5 instead of 3:2. Looks small; costs ~1.4% extra house edge — turns a winnable game into a slow-loss machine.
Stand on hard 17+
Why · Probability you bust hitting on 17 is ~69%. Even against a dealer 10 (worst position), standing has higher EV.
Split aces and 8s. Never split 5s or 10s.
Why · Splitting 8s converts a brutal hand (16) into two playable hands. Splitting 5s gives away a strong starting position (10). Splitting 10s gives away a near-guaranteed win (20).
Common mistakes that cost real money
Our take, scored
Gamsites editorial rating · weighted aggregate combines all four dimensions · see manifesto for the rubric
Casinos with blackjack
How we sourced this
House-edge figures are standard derivations from blackjack basic-strategy math (6-deck, S17/H17 variants). Variants like single-deck or surrender-allowed change edges modestly — see strategy page for chart variants.
Blackjack questions, answered
What is the house edge in blackjack?+
With optimal strategy, Blackjack carries a house edge of ~0.5%. Typical (non-optimal) play runs at ~2–3%. The gap between the two is the recoverable EV — see the strategy section.
Can you beat blackjack with strategy?+
Always use a basic strategy chart Memorized basic strategy is the single biggest EV improvement available in any casino. Five-times-worse house edge without it.
What is the most common mistake in blackjack?+
Hitting hard 17+ Cost: Bust ~69% of the time. Standing wins more long-term even against dealer 10.
Where can I play blackjack?+
Blackjack is carried by 10 of the casinos we cover. See the "where to play" section on this page for the full list with tracked sign-up links.