In Final Fantasy II, rank is a statistic that factors into growth of skills, based on a formula comparing the number of times a character attacks or uses a specific spell. Fighting low-rank enemies at higher skill levels results in minimal or potentially no skill experience gain; conversely, using low-level skills against higher-rank enemies results in higher skill experience gain. The rank of individual enemies can be viewed in the bestiary. Player characters always have a Rank of 2, making targeting allies an effective way grow skills early in the game.
Spell and weapon levels take a certain amount of uses, each awarding a certain number of "points" for that skill to level up. Each time a spell is used or a character attacks with a certain weapon type equipped, a certain amount of "proficiency EXP" is gained with that spell or weapon type. For the first use in a given battle, the proficiency gained is based on the enemy formation's Rank, the character's current proficiency with the spell or weapon type in question, and a static modifier dependent on whether a spell or weapon is being used. All subsequent uses within a single battle will grant 1 point of proficiency experience.
In the NES version, all proficiency ranks require a constant 100 points to reach from the previous rank. In the remakes, the required point thresholds have been set on a curve that gradually increases with each rank.
| Rank | Points (NES) | Points (Remakes) |
|---|---|---|
| 1 | 0 | 0 |
| 2 | 100 | 20 |
| 3 | 100 | 25 |
| 4 | 100 | 25 |
| 5 | 100 | 30 |
| 6 | 100 | 35 |
| 7 | 100 | 40 |
| 8 | 100 | 45 |
| 9 | 100 | 50 |
| 10 | 100 | 60 |
| 11 | 100 | 70 |
| 12 | 100 | 80 |
| 13 | 100 | 90 |
| 14 | 100 | 90 |
| 15 | 100 | 100 |
| 16 | 100 | 100 |