MATK

MATK is arguably the most important stat for a magic-user. It increases the damage dealt by most spells as well as the amount of HP recovered by casting Heal. The three things that affect your MATK the most are your weapon, level and INT.

Calculating MATK
Calculating the minimum and maximum MATK requires the use of two formulas: In the above formulas, Modifier stands for a weapon-type specific multiplier, as follows: This means that for your MATK, it is just as important to choose a suitable weapon as it is to have a high INT. Card effects are applied after the INT and WATK modifiers. Only WATK from the weapon itself and from refines affects MATK - WATK from STR doesn't affect it.
 * Max MATK: ( 10 + base lv + INT / 2 + job lv / 4 + DEX / 6 ) * ( 1 + INT / 100 + (WATK * Modifier) / 100 )
 * Min MATK: ( Max MATK * ( DEX + 2 * AGI )) / ( DEX + 2 * AGI + INT )
 * Rod or Staff: 80% (0.8)
 * Dagger (Ninja with level 5 Nen only): 70% (0.7)
 * Book: 40% (0.4)
 * Dagger or other weapons: 20% (0.2)