Pity & Contract rates
Official pity numbers straight from the in-game contract rules.
The short answer
If you haven't pulled a 5★ in 79 draws, the 80th is a guaranteed 5★. A 4★ or higher is guaranteed every 10 draws. On limited banners the featured 5★ wins 50% of the time; pity does NOT carry between different contract types.
Contract Planner

5★ Justine & Caroline
Example featured 5★ — tap for build
pulls since your last 5★ (0–79)
150 = 1 pull
if on, your next 5★ is guaranteed to be the featured one
Pulls to guaranteed 5★—
Pulls you can afford—
Worst case for featured—
Jewels still needed—
How this was calculated
Official numbers (v4.4)
5★ hard pity: 80
4★ guarantee: 10
Featured rate: 50/50
300 draws = choose a 5★ (first time)
Source: the official in-game contract rules text (v4.4 game data). Note: unlike some gacha games, pity status does not transfer between different contracts of the same ticket type.
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