Cantrips

- All cantrips (0-level spells) can be cast at will.

At-Will Spells

When a wizard gains the ability to cast a new level of spells (at 3rd, 5th, 7th, 9th, 11th, 13th, 15th, and 17th level), he may choose one spell of at least two levels lower than his maximum to cast at-will. At 3rd level, the wizard may choose a 1st-level spell even though it is not at least two levels lower. He no longer needs to prepare that spell, and may cast it an unlimited number of times per day. An at-will spell is cast at the minimum possible level. He may still prepare the spell and cast it at normal caster level if he chooses.

At 10th level, at-will spells are cast at minimum+2 level.

For example, a 3rd-level wizard chooses magic missile as an at-will ability. At 9th level, his at-will magic missile still only deals 1d4+1 damage, but if he prepares the spell it will deal its normal 5d4+5 damage.