# How does one calculate a ship's agility?

According to an equation on http://wiki.eveonline.com/en/wiki/Aligning, a ship's agility modifies the time it takes for a ship to enter warp. However, this 'agility' value is not displayed anywhere in the game (as far as I know).

So, how does one calculate this? I read somewhere it had to do with a ship's mass and inertia values, but I'm not sure on the exact formula.

Agility is not indicated entirely by the inertia modifier. According to this wiki article agility is a product of mass times the inertia modifier of a ship.

Based on this forum post:

The explicit value of agility isn't all that important to know when piloting a ship. The reason agility increases your alignment time is due to the fact that it increases the ability of your ship to turn (i.e. align with warp target). This also reduces the amount of speed you lose while turning and gives you a tighter (and faster) orbit.

Let's look at a Slasher (frigate) vs a Mammoth (industrial), which are both Minmatar ships.

Given that Agility = Mass x Inertia Modifier:

Slasher: Mass 1.075 million kg; Inertia Modifier 2.83; Agility ~3.0

Mammoth: Mass 12.5 million kg; Inertia Modifier 1; Agility 12.5

So you can see that the Mammoth is going to turn a lot slower than the Slasher (as it should). There are also skills, modules, and implants that can affect Agility, so you can't be 100% certain what someone's Agility will be.

## Skills:

Evasive Maneuvering

Spaceship Command

Skills with a * denote skills that only affect ships requiring the skill to pilot them.

## Implants:

The implants list here is old, but it says that there are slot 6 hardwiring implants "Hardwiring - Eifyr and Co. 'Rogue' AY-" which modify agility. They aren't in the list of implants here though.

It probably won't be worth using these implants, depending on how expensive they are and how much you'll actually get out of them.

## Modules:

Inertia Stabilizers reduce the inertia modifier of your ship, which reduces your overall agility. Do note that you can have more than one inertia stabilizer, but their effects will be reduced. You should really only use one if you are going to use one at all.

• Thank you Caesium, your answer was exactly what I was looking for. It's just a bit strange how if one were to replace 'agility' with 'inertia' in this article's formula wiki.eveonline.com/en/wiki/Aligning, one would get the exact align time that EFT displays in it's ship stats window. Does this mean that EFT is using the wrong formula, or that the formula on that article is faulty (and should say inertia instead of agility)? Commented Apr 28, 2013 at 10:38
• I'm glad I could help, but that's a good question. I'm not entirely sure, but it could be either way. The official forum post had a question about agility #394, and the only dev answered it #398. It looks like Pyfa was generating a correct calculation as of 2012.02.12 according to the wiki article formula. Commented Apr 28, 2013 at 15:29

Inertial Modifier (that wing icon) is Agility.

See example on http://wiki.eveonline.com/en/wiki/Acceleration

• But then how come some modules affect 'inertia' and some 'agility', if they are the same thing? Also, on that page it states 'The product of Mass and the Inertia Modifier gives the ship's agility', which implies that they are two separate things. Commented Apr 26, 2013 at 22:23