Casino bonus maths

What is a casino bonus really worth? We compute it.

Take a 100 bonus on a 100 deposit with 35× wagering on the bonus, and play it at even-money roulette bets of 5. You must stake 3,500, which costs 94.59 on average if you get that far. Only 67.4% of players do; the rest go bust first. On average they walk away with 116.17 for the 100 they deposited.

  • Exact maths, checked twice
  • No casino links
  • Free, no sign-up
67.4%of players clear a 35× bonus at roulette before going bust
25×the wagering at which a bonus on a 96% slot costs as much as it gives
27.03the cost of 100 of wagering on roulette counted at 10%, against 4.00 on a 96% slot
4.37what 10% cashback on net losses returns on 1,000 staked at roulette, not 2.70

Calculators

Bonus value calculator

Deposit, bonus, wagering and game: total to stake, average cost and the chance to clear it.

Free spins value

What the spins win on average, and how much survives the wagering.

Cashback value

Why cashback on net losses is worth more than its percentage suggests.

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Wagering requirements

What each multiple costs, and where a bonus stops being worth anything.

Game contribution

Why a low-edge game can be the dearest way to wager.

How we compute

An exact calculation over every balance, checked by simulation.

How we work

We list no offers and link to no casino. Every figure comes from our own code: the chance of clearing a wagering requirement is computed over every possible balance after every bet, and checked against simulated players. No bonus changes the house edge of a game; it changes how much you must stake, and that is what we measure.

Check a bonus before you take it

Enter the deposit, the bonus, the wagering and the game: see the total to stake, the average cost and how often it is cleared.

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