Attack speed
Attack speed in Terraria refers to the rate at which a weapon can attack. Despite many modifiers and effects showing changes to attack or melee speed, attack speed is not an in-game statistic and is instead determined by its reciprocal, known as use time. This is the amount of ticks[1] it takes to swing (attack with) or use an item. If use time increases, attack speed decreases, and vice versa. For example, a weapon with a use time of 30 will have a lower attack speed (slower rate of fire) than a weapon with a use time of 10. As such, any attack speed modifiers will in actuality act as a variable within the use time equation. However, as shown below, for many melee weapons a change in attack speed (and therefore use time) will have effects other than a change in use time.
While almost all weapons can receive attack speed modifiers, such as Quick or Legendary, accessories will only ever provide bonuses to melee speed.
Effects
Melee speed bonuses affect different types of melee weapons and whips(Desktop, Console and Mobile versions) in different ways. For most endgame weapons, it does not increase DPS, as most of them fall into one of the following categories:
Projectile melee weapons
Projectile swords
For projectile swords, melee speed mainly affects the actual swinging animation of the sword itself. It also affects their projectiles' velocity, effectively making projectiles reach further or easier to hit targets at long range. It also has a subtle increase on the projectile's fire rate, and the effect of this boost differs from weapon to weapon.
On the 
Desktop version, 
Console version, and 
Mobile version, in addition to the velocity increase, the Blade of Grass, Night's Edge, Waffle's Iron, Excalibur, True Excalibur, True Night's Edge, Terra Blade, and Horseman's Blade will fire their projectiles every time they are swung, making melee speed bonuses have more benefits on these weapons.[2]
Only projectile
For melee weapons that only shoot projectiles (including Shadowflame Knife(Desktop, Console and Mobile versions), Scourge of the Corruptor, Vampire Knives, and Daybreak(Desktop, Console and Mobile versions)), melee speed will only increase their projectiles' velocity, making them better at hitting targets at long range.
Yoyos
Melee speed bonuses increase the velocity of a yoyo and the length of its string, but not its attack rate. This can be very helpful in the early game, when yoyos are very short and hard to hit bosses with, and against bosses where the player need to keep a distance. The exact multiplier for yoyo string length is 4÷(1+3×(1÷(melee speed))), where melee speed is 1.0 without buffs. Thus, if the player can reach 2× melee speed through buffs, the yoyo string will be 60% longer. This length multiplier is applied after the length increase from Strings or Yoyo Bag.[3]
Flails
Both thrown and launched flails will only have their velocity increased with melee speed bonuses. As a result, they effectively reach further or hit for more often, making them much better at hitting flying targets.
(Desktop, Console and Mobile versions) With melee speed boosts, thrown flails will not attack more often when ⚒ Use / Attack button is held down.
Spears
Spears attack faster with melee speed boosts. They also reach slightly longer, but this increase is negligible.
For spears that create projectiles when attacking (Mushroom Spear, Chlorophyte Partisan, North Pole, Storm Spear(Desktop, Console and Mobile versions), and (Desktop, Console and Mobile versions) The Rotted Fork, Dark Lance, and Gungnir), melee speed will increase the fire rate and the velocity of the projectiles, making the projectiles reach further.
Boomerangs
Boomerangs gain velocity increase from melee speed, making them reach further.
Other melee weapons
All these weapons are Desktop, Console, and Mobile-exclusive.
For the Terragrim, Arkhalis, Jousting Lance, Hallowed Jousting Lance, Shadow Jousting Lance, Sleepy Octopod, Starlight, Sky Dragon's Fury's ⚒ Use / Attack button attack, Solar Eruption, and Zenith, melee speed has no effect on them. However, the Zenith do have a visual change when benefited by melee speed: the amount of swords summoned per attack is reduced when having high melee speed.
For the Sky Dragon's Fury's ⚷ Open / Activate button attack, melee speed will increase both the fire rate and its projectile's velocity.
Whips (Desktop, Console and Mobile versions)
Despite doing summon damage, whips are also affected with melee speed. This will make them attack faster.
Boost gear
Accessories
| Item | Attack speed bonus |
|---|---|
 Fire Gauntlet |
12% |
 Feral Claws |
12% |
 Berserker's Glove(Desktop, Console and Mobile versions) |
12% |
 Power Glove |
12% |
 Mechanical Glove |
12% |
 Celestial Stone |
10% |
 Sun Stone |
10% |
 Moon Stone |
10% |
 Moon Charm |
5.1% |
 Moon Shell |
5.1% |
 Celestial Shell(Desktop, Console and Mobile versions) |
15.1% |
Armor
| Item | Attack speed bonus |
|---|---|
 Molten Greaves |
7% |
 Hallowed Mask |
10% |
 Frost Leggings |
10% |
 Palladium Mask |
12% |
 Orichalcum Mask |
11% |
 Titanium Mask |
9% |
 Beetle Scale Mail |
6% |
 Beetle Leggings |
6% |
 Gi(Desktop, Console, Old-gen console and Mobile versions) |
10% |
 Solar Flare Leggings(Desktop, Console and Mobile versions) |
15% |
 Monk's Bushy Brow Bald Cap(Desktop, Console and Mobile versions) |
20% |
 Shinobi Infiltrator's Torso(Desktop, Console and Mobile versions) |
20% |
 Ancient Hallowed Mask(Desktop, Console and Mobile versions) |
10% |
 Crystal Assassin Pants(Desktop, Console and Mobile versions) |
10% |
 Cobalt armor(with Helmet) |
15% |
 Adamantite armor(with Helmet) |
20% |
 Beetle armor(with Scale Mail) |
up to 30% |
Notes
- (Desktop, Console and Mobile versions) The maximum increased attack speed (for melee) is +158.1% using Monk's Bushy Brow Bald Cap (20%), Shinobi Infiltrator's Torso (20%), Solar Flare Leggings (15%), Exquisitely Stuffed (buff) (10%), Tipsy (buff) (10%), and the five accessories Feral Claws (12%), Power Glove (12%), Mechanical Glove (12%), Celestial Shell (15.1% at night) and Berserker's Glove (12%), each reforged to Violent (20%). In Expert Mode, a Violent Fire Gauntlet can be worn for an extra 16%, with +174.1% total; In Master Mode, an additional Violent accessory can be worn for an extra 4%, with +178.1% total.
- Mining speed of various tools is not affected by melee speed bonuses, and it is only boosted by specialized mining speed bonuses (such as the Mining Potion and Mining armor) and speed bonuses granted by the tool's own modifier, the best of which is Light.
- Enemies' invincibility frames should be taken into consideration when dealing with attack speed. Generally speaking, no invincibility time is applied when referring to projectiles that do not pierce, but those that do pierce or explode are not in this case. Normally it is 1/6 seconds (10 ticks) while there are some exceptions ranging from 5 ticks to 20 ticks.
- Velocity of the following melee damage projectiles is not affected by melee speed:[4]
| Projectile | |||
|---|---|---|---|
| ID | Image | Name | Source |
| 699 |  |
Ghastly Glaive | Ghastly Glaive(Desktop, Console and Mobile versions) |
| 707 |  |
Sky Dragon's Fury | Sky Dragon's Fury(Desktop, Console and Mobile versions) |
| 877 |  |
Jousting Lance | Jousting Lance(Desktop, Console and Mobile versions) |
| 878 |  |
Shadow Jousting Lance | Shadow Jousting Lance(Desktop, Console and Mobile versions) |
| 879 |  |
Hallowed Jousting Lance | Hallowed Jousting Lance(Desktop, Console and Mobile versions) |
| 973 |  |
True Night's Edge | True Night's Edge |
| 985 | |
Terra Beam | Terra Blade |
References
- ↑ A tick is a time unit countable by the software. Most of Terraria's updating logic happens every tick. A tick has the length of 1/60th of a second, hence there are 60 ticks in a second and 3600 ticks in a minute.
- ↑ Information taken from the Desktop 1.4.4.9 source code, methods
SetDefaults1()inTerraria.Item.csandSetDefaults2()inTerraria.Item.cs. - ↑ Information taken from the Desktop 1.4.4.9 source code, method
AI_099_2()inTerraria.Projectile.cs. - ↑ Information taken from the Desktop 1.4.4.9 source code, method
ItemCheck_Shoot()inTerraria.Player.csand fieldSets.NoMeleeSpeedVelocityScalinginTerraria.ID.ProjectileID.cs.