Section 121 Exemption

[John Jones]

I want to start this post regardless of answers; I know I need to consult with an accountant. 

I am trying to understand the 121 exemption. My wife and I have owned our primary residence for over two years. We are about to sell our home and move into an apartment. We should have sizable capital gains from the sale. If I am reading the exemption right, should we be allowed to write off up to 500k in capital gains? 

I appreciate all insight!