dimensional analysis - Do all equations have identical units on the left- and right-hand sides?

Do all equations have $$\text{left hand side unit} = \text{right hand side unit}$$ for example, $$\text{velocity (m/s)} = \text{distance (m) / time (s)},$$ or is there an equation that has different units on the left- and right-hand sides? I would like to consider empirical equations (determined from experimental results) and theoretical equations (derived from basic theory).