What is house edge, and how can it be 0%?
“0% house edge” is a bold claim to see on a casino homepage. Here's what house edge and RTP actually mean, why most crypto casinos sit around 96-98%, and how Duel Originals get to zero.
The short version
House edge is the built-in mathematical advantage a casino has over players, expressed as a percentage of wagers kept over the long run. Duel.com advertises up to 100% RTP on its Originals games — meaning, in theory, the game itself keeps none of that edge, unlike most online casino games.
House edge and RTP are the same number, flipped
Return to Player (RTP) is the percentage of all money wagered on a game that gets paid back to players over a very large number of rounds. House edge is just 100% minus RTP. A slot advertising 96% RTP has a 4% house edge; European roulette's single zero gives it roughly 97.3% RTP and a 2.7% edge. Most crypto casino games — slots, dice, crash-style games — cluster in the 96-98% RTP range, meaning a 2-4% house edge is the industry norm.
So how does a game get to 100% RTP?
A game reaches 0% house edge when its payout table is built so that, mathematically, the expected return exactly equals the total wagered — no percentage is carved out for the house before the math is even run. This is achievable on simple, transparent game types (dice, crash, coin-flip-style Originals) where the odds and multipliers are explicit and can be checked directly, which is also why provably fair verification matters here: a 0% edge claim is only meaningful if you can confirm individual rounds actually resolve using that stated math, not a quietly adjusted one.
If the house doesn't take a cut, where does the money come from?
A casino offering 0%-edge games still needs a business model. Duel.com's public pitch rests on a few pieces: house edge on the much larger third-party slots and live-dealer catalog and sportsbook (which aren't Originals and aren't claimed to be 0%), and skipping the standard matched-deposit bonus with steep wagering requirements that most competitors use to claw back value from new players. In its place, Duel.com runs instant rakeback and leaderboard prize pools — a different mechanism for funding promotions than a hidden edge baked into the games themselves.
Important caveat
The 0% edge claim applies specifically to Duel Originals, not every game on the site. Slots, table games and live dealer titles from third-party studios keep their own standard house edge, same as anywhere else. “Up to 100% RTP” is also a ceiling, not a fixed number for every Original — always check a specific game's stated RTP before assuming it applies. For the complete picture, including licensing and how Duel.com stacks up against other crypto casinos, read our full Duel.com review.
Duel.com questions, answered
What is house edge in simple terms?+
House edge is the average percentage of every wager a casino keeps over the long run, built into the game's math. A 3% house edge means that, averaged across thousands of bets, the casino keeps $3 of every $100 wagered — individual sessions can still swing wildly either way.
What's the difference between house edge and RTP?+
They're two sides of the same number. RTP (Return to Player) is the percentage of wagered money a game pays back over time, and house edge is simply 100% minus RTP. A game with 97% RTP has a 3% house edge; a game with 100% RTP has a 0% house edge.
If the house edge is 0%, how does Duel.com make money?+
Not from skimming the game math on Originals. Duel.com's model leans on other revenue — margin on the wider game catalog and sportsbook, and by not paying out the large matched-deposit bonuses that carry hidden wagering requirements at most casinos. Instead of a bonus with fine print, it offers rakeback and leaderboard prize pools, funded differently than a built-in edge.
Does 0% house edge mean I can't lose money?+
No. A 0% edge is a long-run statistical average, not a guarantee for any single session — variance is still very real, and you can lose your entire bankroll on games with a mathematically fair or even 0% edge. It means the game itself isn't structurally tilted against you, not that losing is impossible.
Try the Originals yourself
Check a round's math against the game's own stated RTP on Duel.com — then verify the round wasn't rigged.
Go to Duel.com ↗This page explains house edge and RTP in general and how Duel.com describes its own Originals. It is maintained by fans and is not written or audited by Duel.com — always verify a specific game's RTP against the casino's own game info before relying on it.