run the slots
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run the slots
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For collector and persistent-progress games — collect N symbols to trigger a bonus. See whether grinding a machine from its current count to the trigger is worth it, and how much being left near the top is worth versus starting fresh.
Symbols Needed
Total required to trigger the bonus
Already Collected
The left machine's current count
Collect Rate
Spins per symbol, as "1 in M"
Bet & Bonus Value
Per-spin wager and the bonus payout
About the Grind Cost
Grind cost is the EXPECTED theoretical base-game loss over the spins needed to collect the remaining symbols. It ignores variance and risk-of-ruin and assumes a constant per-spin collect probability — true for most persistent-collector games, though some weight the rate differently. Conditions vary by game version and casino.
+$48.08
Expected Value
$48.08
+EV of $48.08 — bonus value beats the grind cost.
The bonus is worth more than the expected cost to grind it out.
Symbols Remaining
2
Symbols left to collect before the bonus triggers.
Expected Spins to Trigger
16
Average spins to collect the remaining symbols.
Grind Cost
$1.92
Expected theoretical base-game loss over those spins.
Left-Machine Premium
$3.84
Value of inheriting progress vs. starting from zero.
Inputs
Total symbols required to trigger the bonus.
The left machine's current count on the meter.
Spins per collected symbol. A symbol every 8 spins = 8.
What you'll wager per spin while grinding.
What the triggered bonus is worth, on average.
Base-game RTP while grinding. Higher = cheaper grind.
Collector games make you accumulate a set number of symbols before a bonus triggers, and that progress stays on the machine. The grind cost is expected spins × bet × (1 − base RTP), where expected spins to collect the remaining symbols is remaining ÷ collect rate. Expected value is the bonus value minus that grind cost.
The left-machine premium is the EV difference between continuing from the current count and starting from zero — the value of the progress the last player paid to build.
Grind cost is the EXPECTED theoretical loss. It ignores variance and risk-of-ruin and assumes a constant per-spin collect probability — true for most persistent-collector games, but not all.