Decide whether to grind for a target roll or chase an upgrade first.
Luck & drop-rate calculator
Player-input calculator that turns stacked Luck + Index + Group 2x + Consumables into effective drop odds.
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Questions players ask
How is luck calculated in Build a base RNG?
The math follows the Roblox DevForum convention: rollAfterLuck = math.pow(roll, 1/luck). The wiki's calculator uses the equivalent closed form p_eff = 1 - (1 - p_base)^L_eff.
How do you get shiny / galaxy variants?
Shiny Hunter (330 R$) and Galaxy Hunter (640 R$) gamepasses lift variant-tier odds independently of the main rarity odds. They never fold into the headline N_eff figure — the calculator renders them as a separate row.
Does the Slungpy Games Roblox group 2x Luck count?
Yes — and it is permanent. The calculator treats it as L_multiplicative = ×2.0 in addition to L_additive = +1.0, which is the largest free L_eff boost in the game.
Can the math.pow convention go above 100%?
By construction, p_eff is clamped to [0, 1]. For very high L_eff on a small N_base (e.g. Wood Block 1/3), p_eff saturates at 1.0 — the calculator surfaces a 'guaranteed next roll' note instead of a percentile.