Must drop
For an ordinary progressive, a big pool is just a big number. A must drop pool is different: the operator has committed to paying it before a stated ceiling, so the payout is guaranteed inside a known amount of remaining play, and a high value really does raise what a spin is worth. The arithmetic is three lines. The reason it is rarely usable is that two of its four inputs are not published.
A guaranteed payout divided by shrinking remaining play is the only real jackpot edge.
What a spin returns when the pool has to be paid before a ceiling
Enter the four numbers. Two of them come off the screen and two have to be published by the operator, which is the whole difficulty.
Three lines of arithmetic and three assumptions, all stated
Write the pool now as P, the ceiling as C and the contribution rate as r. The pool has to be paid out before it reaches C, so the network can only stake a further (C - P) / r before the payout is forced. Call that T.
If the drop lands at a uniformly random point inside that remaining turnover, the expected turnover before it happens is T / 2 and the expected size of the pool when it lands is (P + C) / 2. Your share of it is your share of the turnover. Putting those together, the jackpot returns r (P + C) / (C - P) per ringgit you stake.
That expression behaves the way it should. With an empty pool it collapses to r, which is exactly the contribution rate and exactly what the long run gives everybody. As P climbs toward C it grows without limit, because the same guaranteed payout is being divided among an ever smaller amount of remaining play.
The base game returns the advertised RTP minus r, since the contribution was taken out of that figure rather than added to it. Add the two and you have the total expected return per ringgit staked. Above 100% the pool is worth more than it costs to chase.
A positive expected return here is not a plan. It says that if this exact situation were repeated an enormous number of times the average would come out ahead. You will face it once, the variance is dominated by a single rare event, and the ordinary outcome of playing a positive expectation must drop is still losing the money.
Two of the four inputs are almost never published
The pool value is on screen. The advertised RTP is usually findable. The ceiling and the contribution rate are the two that decide the entire answer, and those are the two operators leave out.
Without a stated ceiling there is no must drop at all, only a progressive that somebody described as one. Without a contribution rate the remaining turnover cannot be computed, and every figure above becomes a guess dressed as a calculation.
So the practical use of this page is narrow and worth saying plainly. Where an operator does publish both, you can check whether the offer in front of you is what it claims. Where it does not, the correct conclusion is that the offer cannot be evaluated, which is a finding rather than a failure.
We have not found a published ceiling or contribution rate for the 918Kiss pools. Any figure you enter for those two is your own estimate, and the tiles above are only as good as it.
Frequently asked
A progressive pool with a stated ceiling it cannot pass. Because the operator has committed to paying it out before that point, the payout is guaranteed within a known amount of remaining play, which is what makes the current value meaningful in a way an ordinary progressive's value is not.
It can, and the calculator shows where the crossover sits for the inputs you enter. It requires a genuine published ceiling and a genuine contribution rate. It also requires you to keep playing until the drop, and the ordinary outcome even with a positive expectation is that you lose the money and somebody else wins the pool.
Because if the drop point is drawn uniformly inside the remaining window, the expected amount of play before it happens is half the window and the expected pool size at that moment is halfway between the current value and the ceiling. Those two halves cancel, which is why the final expression is the tidy one shown in the working.
We have not found them published for the 918Kiss pools. If an operator does publish both, that is a genuinely checkable commitment and it is worth more than any estimate. If it does not, the honest position is that the offer cannot be evaluated rather than that it is good or bad.
The numbers this calculation depends on
Three of the four inputs come from somewhere else, and each of those has its own page.
Provider quoted figures for 47 titles with sources. The base game return is that number minus the contribution rate, not the number itself.
Cost per spin and per hour while you sit through the remaining window. That cost is real and it is paid whether or not the pool lands on you.
For pools with no published ceiling, the only thing left is where they have actually been won before. That range has to be built from recorded drops.
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