Online Casino Games: Types, Odds and How They Work

Online casino games fall into a handful of families: slots, table games such as roulette, blackjack and baccarat, video poker, and live dealer tables streamed from a studio. Each family works differently. Some are pure chance with a fixed return set by the game designer, others reward correct decisions, and the house edge ranges from under 1% to more than 10% depending on the game and the bet you choose. This page gives you a quick map of each type, the numbers that matter, and links to our detailed guides.

Casino games are for adults only: 18+ (higher in some countries). If you play for money, decide on a limit before you start; our responsible gambling page lists the tools and free helplines.

Game types at a glance

House edge is the share of each stake the game keeps on average over a very large number of rounds. It says nothing about a single session: short-term results swing widely in both directions.

Slots

Slots are the largest category in every online casino lobby. The result of each spin comes from a certified random number generator, so there is no skill element and no pattern to find. What you can choose is the game: its return to player (RTP), its volatility (how often and how big the wins are), and its features such as free spins, multipliers or Megaways reels. Many studios supply the same title in several RTP versions, so the figure in a game’s help screen at your casino is the one that counts. Our free slots page explains RTP, volatility and bonus maths, and the slots guide covers history and practical tips.

A few slot reviews with full RTP and feature checks: Flaming Hot Extreme, Great Adventure, Cheng Gong, Tiara, Ronin and DragonSphere.

Roulette

Roulette is a wheel game where every bet on the same wheel carries almost the same house edge. The wheel type matters far more than the bet: European and French wheels have a single zero (2.70% edge), American wheels add a double zero (5.26%). French tables with the la partage rule halve the loss on even-money bets when zero lands, which brings those bets down to 1.35%. Variants with extra multipliers usually pay for them by lowering the standard straight-up payout. Read more on our roulette page and in the roulette guide.

Blackjack

Blackjack is the classic table game where your decisions change the odds. Played with basic strategy (the mathematically best play for each hand), common rules give the casino an edge of roughly 0.5%. Rules move that number: a table paying 6 to 5 on blackjack instead of 3 to 2 adds about 1.4 percentage points, and side bets usually carry a much higher edge than the main game. See our blackjack page and the blackjack guide for strategy charts and rule checks.

Baccarat

Baccarat looks formal, but there are no player decisions after the bet: cards are drawn by fixed rules. You choose banker, player or tie. The banker bet has the lowest edge (1.06%, after the usual 5% commission on banker wins), the player bet is close behind at 1.24%, and the tie bet paying 8 to 1 is one of the worst bets in the casino at 14.36%. No-commission tables change the banker payout on certain totals, so check the table rules before you sit down.

Video poker

Video poker deals five cards from a virtual deck; you choose which to hold and draw once. Because the deck is fixed and the pay table is shown on screen, the return can be calculated exactly. Full-pay 9/6 Jacks or Better returns 99.54% with perfect play, while the common 8/5 version drops to about 97.3%. Reading the pay table is the single most useful habit; our video poker page explains how.

Live dealer games

Live dealer tables stream real roulette wheels, card shoes and game shows from a studio, with bets placed through an on-screen interface. The rules and house edge follow the underlying game, so live European roulette has the same 2.70% edge as the digital version. Game show titles add multipliers and bonus rounds and usually carry a higher edge than the classic tables. Live games are not available in demo mode, so learn the rules on the digital version first.

Who makes the games

Casinos rarely build their own games. They licence them from studios that are tested and certified in each regulated market. The studio determines the RTP versions on offer and the features; the casino chooses which version to run. Our game providers page lists the main studios and the groups that own them.

Playing safely

Rules differ by country. In Great Britain, online slots have a maximum stake of £5 per spin, or £2 for players aged 18 to 24, and features such as autoplay and spins faster than 2.5 seconds are banned. Elsewhere the limits may be looser or missing, so it is worth setting your own: a deposit limit, a session time limit, and a firm rule never to chase losses. Free help is available from GamCare and BeGambleAware in the UK and from the services listed here for other countries.