Game Rules — JOKR Originals

Version 1.0 — Last updated: 2026-10-07. Operated by JOKR Labs.

This page forms part of the Terms of Service. It states, for each of the six games we operate on our own servers (the "JOKR Originals"), the complete written rules and the return to player (RTP). The same rules and the same figures are shown in the ℹ️ panel inside each game. The English version prevails over any translation.

Operator entity details will be published here upon completion of licensing.

1. How to read the RTP

1.1. The RTP is the share of all stakes returned to players over a very large number of games. It is measured by simulation of at least 100,000 games per title under the rules below, and the published figure is never rounded upwards. Where the return depends on how you play (BlackJOKR, Crash, Mines), the note next to the figure says which strategy or mix it was measured on.

1.2. There is no hidden mechanism in any Original: every house advantage is one of the written rules below. Your actual results over a session can differ widely from the RTP.

1.3. Rakeback (up to 15 % of the house edge, see the Promotions page) is paid on top of the game return and is not included in the RTP figures.

2. BlackJOKR

6 decks, shuffled before every hand.
The dealer draws to 16 and stands on all 17s, including soft 17.
Blackjack pays 6:5.
The dealer wins all ties, including blackjack against blackjack.
Double on any two cards, including after a split (one card is dealt).
Split up to 4 hands; split aces receive one card each; 21 after a split is not a blackjack.
No insurance, no surrender. The dealer does not check for blackjack: a dealer blackjack beats every hand, doubles and splits included.
Side bets (Perfect Pairs, 21+3) are settled on your first two cards and the dealer’s face-up card, per their paytable.

The theoretical return to player for this game is 90% (with optimal basic strategy for these rules). Rakeback of up to 15 % is paid on top and is not included in this figure.

3. JOKR Duel

Three cards: Red beats Orange, Orange beats Blue, Blue beats Red.
First to win 3 rounds wins the match. A round where both cards are the same does not count.
Against the house, every house card is fixed before the match starts: it is derived from a secret seed (HMAC-SHA256 of the seed, the game id and the round number, each card with equal odds). The SHA-256 hash of the seed is shown before you play and the seed is revealed when the match ends, so you can check every house card.
Against the house, the winner takes the pot (both stakes) minus a 20 % house fee: a win pays 1.6× your stake. Player-versus-player matches have no fee.

The theoretical return to player for this game is 80% (matches against the house). Rakeback of up to 15 % is paid on top and is not included in this figure.

4. JOKR Ballz

Each ball costs $0.36; a match holds up to 100 balls.
All balls race on the same track; the first ball through the finish wins the match for its owner.
The winner receives the whole pot: every ball in the match × the ball price. The house takes nothing.
House players (bots) may enter with more balls than you. Every ball has the same chance, so your odds are exactly your share of the balls and the expected return is 100 %.
If no ball finishes within 3 minutes, the winner is drawn at random, weighted by number of balls.

The theoretical return to player for this game is 100% (no house edge). Rakeback of up to 15 % is paid on top and is not included in this figure.

5. JOKR Spin

European wheel: 37 pockets (0–36), single zero.
Payouts: straight 35:1, split 17:1, street 11:1, corner 8:1, six line 5:1, dozens and columns 2:1, red/black, odd/even and 1–18/19–36 1:1. Zero loses every outside bet.
Before each spin the SHA-256 hash of the server seed for that spin is shown. The pocket is HMAC-SHA256(seed) reduced to 0–36 without bias (equal odds), and the seed is revealed after the spin so you can recompute the result.

The theoretical return to player for this game is 97.3% (every bet type). Rakeback of up to 15 % is paid on top and is not included in this figure.

6. JOKR Crash

The multiplier rises from 1.00× until the round crashes. Cash out before the crash to win your stake × the multiplier at that moment; an auto cash-out pays exactly its target when the target is below the crash point.
Crash point = floor(100 × 0.9 × 2^52 ÷ (2^52 − h)) ÷ 100, where h is the first 52 bits of HMAC-SHA256(seed, salt). It is never below 1.00× and is capped at 1,000×; the maximum win per round is $2,500 (max bet $120).
The SHA-256 hash of seed + salt is published before betting opens; both values are revealed after the crash.
Expected return for a cash-out at t× is 0.9 × t ÷ (t + 0.01): from 89.1 % at 1.01× to 89.9 % at high targets.

The theoretical return to player for this game is 89.3% (measured on the actual mix of cash-out targets). Rakeback of up to 15 % is paid on top and is not included in this figure.

7. JOKR Mines

5×5 grid with 1 to 20 mines. Each safe tile raises the multiplier; cash out at any time.
Multiplier after k safe tiles = 0.9 × fair odds, rounded down to 0.01 (fair odds = 1 ÷ probability of k safe picks).
Maximum win $600 per game.
The mine layout comes from an HMAC-SHA256 stream of a seed committed by its SHA-256 hash when the game starts; seed and salt are revealed when the game ends.

The theoretical return to player for this game is 89.9% (measured on the actual mix of grids; 89.3 % to 90.0 % depending on the grid). Rakeback of up to 15 % is paid on top and is not included in this figure.

8. Records and disputes

8.1. Every hand, round, spin and match is recorded on our servers with its stake, outcome and payout, and — for the commit-reveal games (Duel against the house, Spin, Crash, Mines) — with the committed hash and the revealed seed.

8.2. If you believe a game did not follow these rules, contact JOKR Support — the in-app support chat ("Contact support" in the footer of any main tab) or [email protected] with the game and the time of the round. We will check the server record and answer with the recorded values.