Difficulty Class (DC)
A saving throw against an effect has a Difficulty Class (DC) determined by the effect. For most class features, the DC of an effect you create equals 10 + half your class level + your key ability score modifier. For spells, this is 10 + the level of the spell + your key ability score modifier. See page 181 to find the DC for weapon special properties and critical hit effects. The description of an effect from an item normally lists a saving throw DC.
Source
Core Rulebook pg. 241
