Bonus cost calculator

What a bonus really costs the casino: a behaviour model of thousands of players, calculated in your browser.

Bonus terms

€
%
€
€
€
€
0 means no cap
€
The player plays their own money too, first

Wagering

x
Usually yes: the player bets their own money first, and those bets count toward the wager too
In bonus multiples: 1x on a €100 bonus means no more than €100 to withdraw

Game and player

%
€
Player behaviour
%
The share of players who withdraw once their balance grows and lose the bonus
x
How many spins a player is ready to play for the bonus: half of the players have less patience, half have more

By default the model is calibrated to the market: about 12% of players complete x30 and about 7% complete x40.

The bonus costs the casino
...
per player who got the bonus

Bonus cost is the bonus money players will be able to withdraw. You cannot know in advance who will finish the wager, so we average it over everyone who got the bonus.

Budget for a group of players

players

Where the players go

    %

    How the cost depends on the wager

    Same bonus and same players, only the wager differs. The cost is per player who got the bonus. Your row is highlighted: if you change only the wager, the numbers stay the same and the highlight moves.

    WagerCost per playerCostFinishA finisher takesTakes
    Terms in plain words
    Bonus cost
    The bonus money players can withdraw: the bonus balance that turned into real money after wagering, after the max cashout. In reports this is Bonus Cost.
    Finished
    Completed the wager before running out of balance or patience, without cashing out early. Only finishers get money from the bonus.
    GGR
    Bets minus wins: how much real money players lost to the casino. Bonus money enters GGR only once it becomes real.
    Did the bonus pay off in the sessions
    How much the bonus raised the GGR of these sessions, minus its cost. A minus does not mean the bonus is bad: it works for retention and the next deposits, so bonuses are judged by Bonus Rate over a month.
    Bonus Rate
    The cost of all bonuses for a period divided by GGR for the same period. The threshold depends on your margin, you set it.
    In 8 cases out of 10
    If you gave the bonus to many identical groups, 8 groups out of 10 would land in this range. The smaller the group, the wider it is: with 100 players one big win moves the budget noticeably.
    Wager
    How many times the bonus must be played through before it can be withdrawn. x30 on a €100 bonus means €3,000 in bets. If the wager is counted on deposit plus bonus, the turnover is bigger.
    RTP
    The share of bets a slot pays back to players over the long run. At 96% RTP a player loses €4 on average for every €100 bet.
    Volatility
    How much the wins swing. With high volatility wins are rarer but bigger: the balance hits zero more often, but finishers take more.
    Max cashout
    The most a player can withdraw from the bonus after wagering, in bonus multiples. 1x on a €100 bonus means no more than €100.

    Market check

    10-14% of players complete x30, 6-9% complete x40: an analytics vendor estimate, data not disclosed. The model with default settings gives 12% and 7%.
    Spain, Q3 2025: 35% of bonuses granted turned into real winnings.

    An estimate for professionals, not financial advice. Nothing is sent anywhere: the calculation link keeps the terms in the page address.

    How the calculator works

    Behaviour model

    Each calculation simulates 8,000 bonus sessions. A player bets their own money first, then the bonus money. Some players withdraw as soon as their balance doubles, and the bonus is forfeited. Each has their own patience: some quit wagering after a hundred spins, others play thousands.

    Checked against the market

    With default settings 12% of players complete x30 and about 7% complete x40, in line with market estimates. The slot behaves like a real one: a win on roughly every fourth spin, a spread set by volatility and an average return equal to RTP.

    What to count separately

    The calculator shows one bonus session. Later deposits, retention and LTV are not included, which is why there is a Bonus Rate check for the period. This is an estimate for professionals, not financial advice.