The amounts you mention are for the sale of a personal residence ONLY.
These are NOT tax credits!
These are the amounts that are excluded from capital gain taxes when a persona residence is sold.
The first $250,000 of "profit" or "capital gain" is NOT taxable for a single person.
The first $500,000 of "profit" or "capital gain" is not taxable for a married couple.
So one would NOT pay income tax on these amounts as these amounts are EXCLUDED from income tax, this is different than a tax credit.
This is a federal tax law that applies everywhere in the US.
The State of CA recognizes this exclusion too.
Hope this helps.