A 101-number colour wheel, not a 37-pocket table
Gamdom Roulette is one of Gamdom's in-house Originals. The help centre calls it "Gamdom's unique take on the classic casino game. Bets are placed on a colour (Red, Black or Green), with outcomes generated randomly each round" (Gamdom Originals article, 12 Nov 2026). There are no numbers to pick, no dozens and no splits: a shared round produces one result for everyone, and you are paid if it has your colour.
| Item | What Gamdom states | Where |
|---|---|---|
| Bets | Red, Black or Green | Help centre, "Gamdom Originals" (12 Nov 2026) |
| Results | A number from 0 to 100: 0 green, 1 to 50 red, 51 to 100 black | Roulette sample code linked from the fairness page (12 Nov 2026) |
| Payouts | "Red/Black offers a 2x return"; the green figure is filled in by the game | In-game rules text (12 Nov 2026) |
| RTP | "100% RTP up to $5,000 in wagers, dropping to 99% thereafter" | Roulette game page (1 Nov 2026) |
| Minimum bet | $0.01 | Help centre, "Minimum and maximum bet amounts" (12 Nov 2026) |
| Maximum bet | Red/Black $600,000; Green $200,000 | Same help-centre article (12 Nov 2026) |
| Maximum win | "Capped at $500,000" from a single bet | Roulette game page (1 Nov 2026) |
| Modes | Standard (manual) and Auto-Bet | Help centre, "Gamdom Originals" (12 Nov 2026) |
| Fairness | Chain of SHA-256 hashes played in reverse, with a published commitment | Fairness page (12 Nov 2026) |
The help-centre limits article and the game page do not line up neatly: a $600,000 bet on red would win more than the $500,000 the game page gives as the cap on a single bet's win. The limits article was last updated more than ten months before it was read. The bet panel shows the stake limit that applies to your account, and that is the figure to go by.
What each colour returns: arithmetic from the sample code
Gamdom's sample code maps a round's result onto 101 numbers and three colours. Red and black each hold 50 numbers and pay 2x:
| Bet | Wins on | Win chance | Pays | Return | Cost per $100 wagered |
|---|---|---|---|---|---|
| Red | Numbers 1 to 50 | 50 in 101, 49.50% | 2x | 99.01% | $0.99 |
| Black | Numbers 51 to 100 | 50 in 101, 49.50% | 2x | 99.01% | $0.99 |
| Green | Number 0 | 1 in 101, 0.99% | 100x at the same price (see below) | 99.01% | $0.99 |
Arithmetic from the number ranges in Gamdom’s roulette sample code and the 2x colour payout in the in-game rules. Payouts include the stake.
A red or black bet returns 100/101 of the stake on average, 99.01%, a house edge of 0.99%. The entire edge is the single green number: 50 numbers win, 51 lose. That fits the 99% Gamdom states for the game after the daily allowance. The in-game text leaves the green payout as a value the game fills in; at the same 99.01% price a 1-in-101 bet pays 100x, and the bet panel shows the figure in force.
For comparison, an even-money bet on a single-zero roulette wheel wins on 18 of 37 pockets and costs 2.70% of the stake, and Roobet's 15-tile colour wheel costs 6.67%. Per dollar wagered, Gamdom's wheel is the cheapest of the four roulette-named games compared on this page, by a wide margin.
Zero Edge: the first $5,000 of the day
Gamdom adds a rebate on top of the game's own maths. The help centre describes it under Originals: "Zero Edge: A small portion of your bets is paid back instantly on certain games, for the first $5,000 wagered." The King of the Hill article gives the size: that portion "already runs at an effective 100% RTP, with a 1% value returned to you through Instant Rakeback".
The arithmetic matches the claim on this game. A colour bet returns 99.01% from the wheel; a 1% rebate on the amount wagered brings the total to about 100%. Once the allowance is used the rebate stops and the game runs at its own 99.01% until the allowance resets. Two conditions come with it, both from Gamdom's help centre: wagering inside the allowance earns no King of the Hill points ("the first $5,000 wagered across any in-house games won't count toward KOTH points"), and while a deposit bonus is being wagered "Rakeback isn't generated" at all.
A game with no edge is not a way to win. It is a game where the average result is zero and the swings are whatever the stakes make them. $5,000 of red-or-black bets at $50 each is 100 rounds, and the spread of outcomes over 100 even-money rounds is around plus or minus $500, with or without the rebate.
Streaks on a shared wheel
Every round's number comes from that round's hash alone, so the wheel has no memory. Gaps still appear constantly:
| Rounds in a row | No green | No red (or no black) |
|---|---|---|
| 5 | 95.1% | 3.28% |
| 10 | 90.5% | 0.11% |
| 50 | 60.8% | Under 0.01% |
| 101 | 36.6% | Under 0.01% |
| 300 | 5.1% | Under 0.01% |
Arithmetic: 100/101 per round for green to miss, 51/101 for one colour to miss.
Green stays away for 101 rounds in a row about 37% of the time, and for 300 rounds about one time in twenty. Ten rounds without red come up about once in 930 ten-round windows. Auto-Bet "with a fixed strategy", as the help centre puts it, repeats bets automatically; whatever the strategy does with the stake after a loss, each bet it places still returns 99.01% on average, so the sequence returns 99.01% of everything staked.
How a round is generated
Gamdom's fairness page sets out the model: "We have generated a chain of 10 million SHA256 hashes for each game, starting with a server secret that has been repeatedly fed the output of SHA256 back into itself 10 million times." The chain is played backwards: "the game server is playing through this chain of hashes in reverse order". There is no player seed in this game. All bets in a round share one hash.
The sample code linked from that page turns a round's hash into a number in three lines:
seed = SHA-256( JSON text of [ round hash, salt ] )
number = (first 13 hex characters of seed, as a number) mod 101
0 → green 1 to 50 → red 51 to 100 → black
previous round hash = SHA-256(round hash)
The salt is the fixed value 0000000000000000019ee980eb5c43e1e4e9d16bee8bb96d9ee691fa2c49c219, which is the hash of Bitcoin block 453,235, mined on 16 February 2017. The code carries its own caveat next to the modulo step: "warning: slightly biased because of modulo!" The bias is real and negligible: thirteen hex characters hold about 4.5 quadrillion values, which do not divide evenly by 101, so some numbers are favoured by less than one part in ten trillion.
The sample-code page also notes "For game results before 19.11.2025 16:30 UTC" and links an older verifier, so rounds before that date are checked with different code.
The published commitment, and why to save it
A hash chain protects players only if its end point is public before the rounds are played. Gamdom's fairness page publishes one for each chain game. On 12 Nov 2026 the Roulette line read: "The SHA256 of the final hash for Roulette starting at game 12,332,529 is: a3259bcf0897dc8f8da61fb34e61256c4d1d3e7aac996e9268c06d78d306fb9a". The page explains the purpose: "By publicising it here we are preventing any ability to pick an alternate SHA256 chain."
The value on that page changes when Gamdom starts a new chain. On 1 Nov 2026 the same line named a chain "starting at game 11,761,475" with a different hash. A commitment is worth something to you only if you recorded it before your rounds, so copy the line from the fairness page when you start playing; a round you verify later should hash back to the value you saved.
Verifying a round
- After a round, copy its hash from the game. Gamdom says: "We're publishing a game's hash immediately after the game ends."
- Open the Roulette sample code from the fairness page and paste the hash. It lists the result for that round and the rounds before it.
- Check the chain link yourself if you wish: "By checking that the SHA256 hash of that game's hash is the game's hash of the previous game you can make sure that we were not able to modify the result."
- Compare the numbers and colours with the game's history.
Our own tools do not include this game. The roulette verifier reproduces the 37-pocket wheels on Stake and Shuffle from a seed pair, which is a different construction, and the roulette calculator prices 37- and 38-pocket wheels. For Gamdom Roulette the sample code on Gamdom's fairness page is the tool to use.
Bonuses, rakeback and this game
Gamdom's Deposit Bonus Guide lists what counts toward a bonus's wagering, and the short version for this page is one line: "Originals and a few other titles are excluded." Roulette bets placed while a deposit bonus is active do not move the requirement. Outside a bonus, Originals wagering feeds Gamdom's rakeback, whose formula the help centre says "is not shared publicly". Details are on the Gamdom promo code page.
Gamdom's lobby also carries studio live-dealer roulette. Those tables use physical wheels with standard layouts and standard edges, 2.70% with one zero and 5.26% with two, and nothing on this page applies to them.
Gamdom's wheel against Stake, Shuffle and Roobet
| Gamdom | Stake | Shuffle | Roobet | |
|---|---|---|---|---|
| Game | 101-number colour wheel | 37-pocket European wheel | 37-pocket European wheel | 15-tile colour wheel |
| Even-money bet wins on | 50 of 101 | 18 of 37 | 18 of 37 | 7 of 15 |
| Return on that bet | 99.01% | 97.30% | 97.30% | 93.33% |
| Cost per $100 wagered | $0.99 | $2.70 | $2.70 | $6.67 |
| Stated RTP | 99%, or 100% inside the daily allowance | 97.30% | 97.30% | None |
| Round | Shared, hash chain, no player seed | Private spin from your seeds | Private spin from your seeds | Shared, hash chain |
| Salt behind the chain | Bitcoin block from 2017 | Not applicable | Not applicable | Ethereum block named before it was mined |
Stake: fairness documentation and game page, 1 Nov 2026. Shuffle: game page and help centre, 12 Nov 2026. Roobet: help centre and verifier, 12 Nov 2026. Returns are arithmetic from each game’s payouts.
On price Gamdom's wheel wins this comparison easily. The two chain games differ in construction: Roobet's salt is a block that did not exist when its chain was committed, while Gamdom's is a block from years earlier, so on Gamdom the protection rests entirely on the chain commitment published on the fairness page. Stake and Shuffle sidestep the question with a seed you set yourself.
Sources: Gamdom fairness page and the Roulette sample code it links (12 Nov 2026; fairness page also as of 1 Nov 2026); Gamdom help centre, Gamdom Originals, minimum and maximum bet amounts, King of the Hill and Deposit Bonus Guide (12 Nov 2026); Gamdom Roulette game page (1 Nov 2026); Bitcoin block 453,235. Returns and streak chances are our arithmetic.
Licence, KYC and withdrawal terms are in the Gamdom review.