Base Damage Rating

All weapons display a Base Damage Rating on the weapon's information page. This gives you a general idea of the effectiveness of a weapon’s "base" damage. It is calculated from the weapon's damage dice, enhancement and modified by the weapon's crit profile.

The Base damage rating is calculated by taking the average result for the weapon's damage dice roll (i.e. a weapon that does 2d6 has an average of 7) and working out the average for each possible result of a d20 roll, applying the weapons crit profile as appropriate (assumes a threat on the d20 is confirmed).

Hence a plain Great Sword (2d6, 19-20 x2) has a Base Damage Rating of (7 + 7 + ... + 7 + 14 + 14)/20. 154 / 20 = 7.7
 * This can also be expressed as ((7*18)+(14*2))=154. 1-18 being normal hits and 19-20 being critical hits.

BDR = (Average Damage)*(1+0.05*(21-Low end of Crit Range)*(Crit Mulitplier-1)) In the above example: (7)*(1+0.05*(21-19)*(2-1)) = 7.7
 * You can calculate the BDR with this formula:

It’s important to note that this number does not include: (This is why it's called the *Base* Damage Rating.)
 * Damage done by additional properties like Holy, Pure Good, Acid, Flaming, etc.
 * Strength modifier.
 * Situational modifiers.

Since damage from weapon properties plays such a large role in DDO, the Base Damage Rating of a weapon will play a lesser role in determining whether weapon X is better than weapon Y in many cases.