What is war weight (WW) and why is it important?

When a clan goes to war, SuperCell uses a formula to calculate the average strength of those members a clan has placed in its war lineup.  It then tries to find another clan who is looking for war who has approximately the same average strength.  This makes sense.  Ideally, every clan should be warring against a comparable clan.

(The outcome isn’t always fair, but as often as we get paired with a stronger clan, we should be paired with a weaker one; so even though any given war may not be a equal match, it hopefully comes out close to even in the long run.)

The average strength of a clan’s lineup is sometimes called its average war weight.  As you would expect, the makeup of each participant member affects the clan’s average.  The stronger a member’s war weight, the higher his clan’s average.

Presumably everything about your base and army affects your war weight.  Which troops you have, the level of each troop, what defensive units you have, the level of each defensive unit, walls … everything. 

It seems that the formula is more sensitive to upgrades in defense than offense; that is, upgrading defense increases war weight more than upgrading troops does. Therefore, many people recommend focusing primarily on offense, at least as a priority.  However, with the late 2017 algorithm change, this is probably no longer be true.

How is War Weight Calculated?

It is somewhat a mystery, yet various sources claim to have a good idea of how it is calculated.

In the link below, there is a chart of what is currently regarded by one expert as the most accurate list of war weights for defensive (and offensive) pieces. These charts are probably now outdated.

Some seem logically obvious, such as the inferno and EA are both very heavy, but others are interesting. An xbow may weigh less than a bomb tower, a wizard tower or mortar. ADs and air sweepers seem to account for very little. From a war perspective, we have heard that mortars and wizard towers are almost heavy; while teslas, archer towers and cannons are more attractive in terms of damage-per-second that they inflict versus weight they incur.

The witch may be the heaviest troop. We now believe that the troops and level of troops impacts war weight more than they used to. Therefore, you might want to avoid unlocking or upgrading troops you don't use, especially if your clan has upgrade perks for donations, in which case your donation ends up being stronger than what you gave (up to the troop max).

Please read the following:

Be sure the scroll down once you get there to see the war weight tables.