Spouse Benefits in SS

[homestead]

Hi all

New here, Does anyone know how to calculate benefits for your spouse at different retirement
dates for the primary earner. Can't find much on ss.gov except that at full retirement age a spouse
can claim 50% of the primary earner benefit at full retirement age. Is it always 50% or is it less
if you RE? Also how does Firecalc handle it when the spouse retires at 62 and at a later time gets
the secondary benefit from the spouse retiring?
Thanks

Homestead