Gacha glossary

Gacha games share a vocabulary but each one bends it a little. These are the terms this site uses on every calculator, defined the way the games actually apply them.

Pity: The counter of pulls made since your last top-rarity drop. Most games use it to protect you: the higher it climbs, the closer you are to a guaranteed drop. It normally resets only when the top rarity appears, not when a banner ends.
Hard pity: The pull on which a top-rarity drop is forced. In Genshin Impact it is pull 90 on the character banner, in Wuthering Waves pull 80, in Arknights pull 99. Reaching it costs a fixed amount of currency, which is why it is the number players save toward.
Soft pity: A range of pulls before hard pity where the per-pull rate jumps sharply and keeps rising. Genshin goes from 0.6 % to about 7 % at pull 74; HSR does the same. Most top-rarity drops land inside this window, so the average is well below the hard cap.
Base rate: The chance of a top-rarity drop on a normal pull, before any pity kicks in: 0.6 % in Genshin and HSR, 0.8 % in Wuthering Waves, 2 % in Arknights, 3 % in Granblue Fantasy.
50/50: On banners with a 50/50, a top-rarity drop is the featured unit half of the time and a standard unit the other half. Losing the flip guarantees that the next top-rarity drop on that banner type is the featured one, and that guarantee carries into future banners.
Guarantee: The state you are in after losing a 50/50: your next top-rarity drop will be the featured unit no matter what. Some games (Wuthering Waves weapons, Honkai Impact 3rd, AFK Journey rate-ups) skip the flip entirely and guarantee the featured unit directly at hard pity.
Rate-up / featured: The unit a limited banner is promoting. It has a boosted share of the top-rarity drops (50 %, 75 % or 100 % depending on the game) and is usually unavailable once the banner ends.
Spark: A deterministic exchange: every pull on a banner grants a token, and after a fixed count (300 in Granblue Fantasy, 200 in Blue Archive, 330 in FGO) you can trade them for the unit you want, regardless of what the gacha gave you. Tokens usually expire with the banner.
Capturing Radiance: Genshin Impact’s hidden streak protection since version 5.0. It makes three 50/50 losses in a row impossible and can trigger earlier at random, lifting the effective featured rate from 50 % to roughly 55 %.
Epitomized Path: Genshin Impact’s weapon-banner targeting: you choose one of the two featured weapons, and after one 5★ weapon that is not your choice, the next 5★ weapon is guaranteed to be it.
Banner: A gacha pool with its own rules and unit lineup — character event, weapon, standard, chronicled, and so on. Each banner type keeps its own pity counter, which is why the calculators here are split by banner.
Multi (10-pull): Ten pulls bought at once. Many games guarantee at least one mid-rarity unit per multi, but the top-rarity chance is exactly the same as ten single pulls — the calculator treats them identically.
F2P: Free-to-play: a player who never buys currency. F2P planning is mostly about knowing how many pulls the game gives per patch and comparing that with the cost of a full pity.
Carry-over: Whether pity survives the end of a banner. In HoYoverse games and most modern gachas it does, within the same banner type; in Fate/Grand Order and Blue Archive the counter is tied to the specific banner and vanishes with it.