Attack depends on Strength and the relevant combat skill with the weapon type currently in use. As of the December 2018 Update Attack derived from Strength is in a 1:1 translation for all main-hand and ranged weapons:
- Attack = 8 + Combat Skill + STR
For weapons in the off-hand, Strength contribution is reduced by half:
Combat Skill translates into Attack in differing skill tiers, similar to Accuracy, and likewise includes Item Level skill bonus for the skill total even though said iLv Skill is not shown in the Skills menu.
Pet: Attack from Pet: STR
Pet's attack derived from their STR is via the same rate as a player's off-hand Strength derivation: