Build a base RNG Roll Calculator
Calculate roll probabilities and luck-adjusted odds for Build a base RNG Roblox with our free probability calculator.
How the Calculator Works
Enter base target rarity odds, number of Rolls, and luck multiplier. The calculator returns probability of at least one hit using complementary probability: P(hit) = 1 - (1-p)^n with adjusted p.
Using Results
If ten Rolls at one percent show only ~9.6% cumulative odds, plan longer sessions or raise luck before complaining about bad RNG. Cross-check rarity estimates.
Limitations
Does not model pity, banner boosts, or tier-specific tables. Use as planning baseline only.
Frequently Asked Questions
What luck value should I enter?
Stack permanent and temporary multipliers — e.g. 2x luck = double effective rate before caps.
Does auto-roll count?
Yes — each auto-roll samples the table once.
Can odds exceed 100%?
Calculator caps displayed probability at 100%.
Is pity included?
Not yet — add manual buffer Rolls if pity exists.