Weapon Level

Weapon Rank is a weapon's ranking, from weakest to strongest, on a scale of E - D - C - B - A - S, with few exceptions. It can be both a weapon stat and a character stat, in which the character must have a weapon rank at or higher than the listed weapon rank to use it in battle. The stat started appears in FE4 through FE13 and replaces the old Weapon Level system used in FE1 and FE3. For a unit to increase their weapon rank, in most games, their rank will increase after using a particular weapon type enough, through a stat known as Weapon Experience. However, this is not always the case.

Sometimes, using weaker weapons is a good idea, such as against enemies much weaker than you, as a means of conserving money. In most cases, a unit cannot advance to S-rank if they have not yet promoted. For example, in Fire Emblem: The Sacred Stones, Joshua can't progress beyond A-rank as a Myrmidon. Most units can also not get an S in more than one weapon type. The Rank of a weapon specifies how difficult the weapon is to wield. In general, weapons with higher Might have a higher Rank, but this not always the case, such as with the Devil Axe.

Weapons with higher ranks also seem to have a greater weight, meaning it is harder to land more than one hit with them, although this is not much of a problem for most units. The higher the weapon rank, generally the more damage it does.

Weapons with higher ranks also cost more, and generally have fewer uses than lower ranked weapons.Fire Emblem: Radiant Dawn introduced the SS ranking, which sits above S, only available to 3rd Tier classes. Additionally, weapons may be of the Prf rank or have no rank at all. Prf-rank weapons are unique to certain characters and can be the most powerful weapons in the game. Weapons with no rank usually function the same as Prf-rank, although in some games it means they can be wielded by anybody no matter their weapon proficiency (yet it is impossible, without using exploits or hacking, to obtain such weapons for yourself as only enemies wield them). Weapons ranked SS are generally earned by defeating a boss, having a person join your group, or going to a certain spot on a map. A good example of this is Stefan, who, when recruited, comes with the SS-ranked Vague Katti, which is also a one-of-a-kind weapon, as all SS ranked weapons are. In that same chapter, if you stand near the center of the map, you can obtain the SS-ranked knife, Baselard.

In Fire Emblem: Seisen no Keifu classes are stuck with the weapon rank for each of their usable weapon types, which is set for each class. This can also be changed, but only by inherited Holy Blood. Minor holy blood will raise the weapon rank of that holy crusader's weapon type by one letter, however, it will do nothing if the base weapon rank is already an A. This is the same with major holy blood, however, instead of by one rank, it will be automatically raised to a * if that class can use that particular weapon.

List of Weapon Ranks
The ranks are as follows:


 * E - Often the starting rank; Iron or bronze weapons
 * D - Steel Weapons
 * C - Special Weapons ('Killing' weapons, or strong against X-type of unit)
 * B - Stronger Special Weapons
 * A - Silver Weapons
 * S - Story Weapons (also other high-end weapons in Radiant Dawn only)
 * SS (only appears in Radiant Dawn) - Story Weapons
 * Prf (Star Weapons)- Weapons without a skill rank that are usually only usable by one character

Note that weapon rank is only applied to Swords, Lances, Axes, Bows, Knives, Tomes, and Staves. Other weapons, such as Ballistae and Dragonstones, do not have a weapon rank.

Weapon Rank bonus
In Fire Emblem: Shadow Dragon, a new weapon rank bonus was added. This increases various effective stats in combat when using the weapon type the user has a high rank in. This does not apply if the wielder is also affected by a Weapon Triangle penalty in the combat, e.g.: a user cannot use their Lance weapon rank bonus when fighting an opponent with an a rank Axe. Fire Emblem: Shin Monshō no Nazo ~Hikari to Kage no Eiyū~ expanded on this mechanic with bonuses to staves also.

Weapon Rank bonus effects
Here are a list of all the combat stats effected by the presence of each type of weapon rank bonus.

Trivia

 * In Sacred Stones, Ross, Amelia, and Ewan, as "trainee" characters begin with weapon ranks of F, the lowest level to appear in the series.