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Formula · n ≈ ln(0.5) / ln(1 − p)

50 / 90 Threshold Calculator

Enter any drop rate and we'll return the packs, tokens and 99% benchmark you need to plan a chase. Budget for the worst case, not the average.

The rule in one line

Every chase is really just two numbers: the packs to 50% chance, and the packs to 90%. Below that is the 99% extreme; use it to plan a budget that survives a bad run.

Longer explainer →

50 / 90 rule

%
Packs → 50%
3,466
69,320
Packs → 90%
11,512
230,240
After 100 packs
1.98%
chance
Reference table

Canonical rates, pre-computed.

RatePacks → 50%Packs → 90%Packs → 99%Context
Rainbow Panda (0.02%)3,46611,51223,024Safari Chroma
Mega Bot (0.03%)2,3117,67515,349Bot Legendary
Red Astronaut (0.05%)1,3864,6059,209Space Chroma
King of Hearts (0.3%)2317671,533Wonderland Legendary
Megalodon (0.6%)116383766Aquatic Legendary
Typical Epic (2%)35114228Cross-pack baseline
Flagship chases

Know the number before you start.

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