The Question Behind the Question
You are standing in front of three very different machines or tables, and you want to know which one is least likely to drain your bankroll. That is a fair question, but it hides a second one: what do you mean by better odds? A game can offer a small built-in disadvantage that grinds slowly, or a large one that hides behind rare, flashy payouts. The answer depends on whether you are measuring the long-run mathematical edge, the shape of the losses, or the chance of a single big win.
Blackjack, keno, and slot machines sit at three different points on that spectrum. One is a comparing card game where your decisions change the outcome. One is a lottery-style draw where the numbers are drawn and you simply wait. One is a random number generator dressed in reels and symbols. Each has its own arithmetic, and each arithmetic behaves differently over an evening.
How the House Edge Is Built Into Each Game
The house edge is the mathematical advantage the operator holds on a given game, expressed as a percentage of each wager. House edge and RTP are complements: they sum to 100% for the same game. A game with a house edge returns, on average, slightly less than the amount wagered over a very large number of plays. That is a long-run statistical average, not a per-session guarantee. In a single session, variance dominates. You can win on a high-edge game and lose on a low-edge one.
Blackjack's edge comes from the rules and from the player's decisions. The objective is a hand total closer to 21 than the dealer's without exceeding it. The dealer acts under fixed constraints, and the player chooses when to hit, stand, double, or split. Published basic-strategy charts derive from the specific rule set in use: deck count, dealer stand rules, doubling and splitting rules. Played with a sound basic strategy under a favourable rule set, blackjack carries one of the lowest house edges on a casino floor. Played by feel, with decisions made on hunches, the edge widens considerably. The game does not fix your edge for you; your choices do part of the work.
Keno is closer to a lottery. You pick numbers, the game draws numbers, and your payout depends on how many match. The house edge on keno is typically among the highest of any game in a casino, because the payout table pays less than the true odds of matching a given number of spots. The gap between the true probability and the posted payout is where the operator's advantage lives. There is no decision you make after the draw that changes anything. The edge is fixed by the pay table before you ever pick a number.
Slot machines sit in between in one sense and at the far end in another. The edge is built into the game's RTP, which is a theoretical percentage of total wagered money a game returns to players over a very large number of spins. The RTP is set in the game's programming and does not change from spin to spin. But volatility changes how that RTP is distributed. High volatility means rarer but larger payouts; low volatility means more frequent but smaller ones. Volatility does not change a game's RTP. A slot with a high RTP and a slot with the same high RTP can feel completely different, because one pays small amounts often and the other pays nothing for long stretches and then a large amount once.
What the Numbers Compare
Here is the structural comparison, game by game, on the dimensions that matter when you are choosing where to sit down.
| Dimension | Blackjack | Keno | Slot Machines |
|---|---|---|---|
| House edge range | Low to moderate, depending on rule set and player decisions | High, fixed by the pay table | Moderate to high, fixed by the game's RTP |
| Player decisions after the game starts | Yes: hit, stand, double, split | No: numbers are drawn after the pick | No: spin outcome is determined by RNG |
| Volatility | Moderate, with swings from doubles and splits | Very high: most draws pay nothing, rare draws pay large | Varies by game: low, medium, or high |
| What changes the edge | Rule set, deck count, player skill | Pay table for the number of spots chosen | Programmed RTP; nothing the player does |
| Pace of play | Slower, human-dealt or table-paced | Fast, especially in video keno | Fast, especially with autoplay |
The table shows why a simple ranking is misleading. Blackjack generally offers the best odds of the three when played with a sound basic strategy under a favourable rule set. But that statement carries two conditions, and both matter. Keno offers the worst odds of the three in most configurations, but it also offers a lottery-style payout shape that some players prefer. Slots sit in a wide band: some slots have RTPs close to a decent blackjack game, and some have RTPs close to keno. The only way to know which slot you are looking at is to check the game's information panel, which is where the operator publishes the RTP for that specific title.
Why the Best-Odds Game Is Not Always the Right Game
Odds are only one input into a decision. The pace of play matters as much as the edge. A game with a low house edge played quickly can cost more per hour than a game with a higher edge played slowly, because the edge applies to every wager. If you are playing blackjack at a full table, you might see 50 to 80 hands an hour. If you are playing a fast video keno game or a slot with autoplay, you might see several hundred rounds in the same hour. The per-wager edge is lower on the blackjack table, but the total amount wagered per hour is higher on the machine. The two effects pull in opposite directions.
There is also the question of what you are buying. A slot machine sells the possibility of a large, rare payout. A keno game sells the same thing, with even longer odds and a higher edge. Blackjack sells a slower, more decision-heavy experience where the edge is lower but the variance is still real. None of these is a way to win. The house edge is built into every one of them, and no betting pattern changes the built-in edge of a negative-expectation game. Progression systems, doubling after losses and similar, redistribute outcomes rather than remove the edge. They change the shape of the losses, not the sign of the expectation.
Reading the Numbers on the Game You Are Playing
If you want to compare odds on the specific games in front of you, you need three pieces of information, and all three are published somewhere.
For a slot machine, open the game's information or help panel. It will show the RTP for that title, usually as a percentage. The RTP is a theoretical percentage of total wagered money a game returns to players over a very large number of spins. It is a long-run statistical average, not a per-session guarantee. The panel may also show the volatility, usually described as low, medium, or high. That tells you how the RTP is distributed, not whether the RTP is good or bad.
For keno, look at the pay table for the number of spots you are choosing. The pay table tells you what each match count pays. The gap between the true probability of a match and the posted payout is the house edge. Different spot counts on the same game can carry different edges, so the pay table is the document that matters. If the pay table is not shown on the machine, it is in the game's rules or help screen.
For blackjack, the relevant document is the table rules. Deck count, dealer stand rules, doubling and splitting rules, and whether surrender is offered all change the house edge. A basic-strategy chart is only as good as the rule set it was built for. A chart built for a single-deck game with the dealer standing on all 17s is not the chart for a six-deck game where the dealer hits soft 17. If you are playing online, the rules are in the game's information panel. If you are at a table, the rules are printed on the felt or posted at the table.
What You Can and Cannot Control
You can control which game you play, how fast you play it, how long you stay, and how much you wager per round. In blackjack, you can control your decisions, and those decisions change the edge. In keno and slots, you cannot change the edge at all; you can only change the pace and the stake.
You cannot control the outcome. No machine is due, no number is hot, and no strategy turns a negative-expectation game into a positive one. The honest way to think about the choice between blackjack, keno, and slots is not which one will win, but which one you understand well enough to know what you are paying for the entertainment. The game with the best odds is the one whose edge you have read, on the specific rule set or pay table in front of you, and whose pace you have matched to the time and money you intend to spend.
FAQ
Does blackjack always have better odds than slots?
Not always. A blackjack game with unfavourable rules and poor player decisions can carry a higher house edge than a slot with a high published RTP. The comparison only holds when you compare a specific blackjack rule set played with a sound basic strategy against a specific slot's RTP. The game's information panel and the table rules are the documents that settle it.
Is keno the worst game in the casino for odds?
Keno generally carries one of the highest house edges on the floor, because the pay table pays less than the true odds of matching a given number of spots. But some side bets on other games can carry even higher edges. The relevant comparison is always between the specific pay table you are playing and the specific alternative game, not between game categories in the abstract.
Can I improve my odds on a slot machine by changing my bet size?
Changing your bet size changes how much you wager per spin, not the RTP of the game. The RTP is set in the game's programming and applies to every spin at every stake, unless the pay table or rules state otherwise. Some progressive jackpots require a maximum-stake bet to qualify, which is a separate condition printed in the game's rules.
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This article is general information about how these mechanics work. It is not legal advice and not a recommendation to gamble or to use any particular operator. Availability and legality differ by jurisdiction — check the rules that apply where you are.