A "wet cell" lead-acid battery that's fully charged and hasn't just been removed from the charger moments ago should be about 12.7v. It'll hold a higher surface charge for some time after being removed from a charger if it has no load, but if you let it sit for a few hours or briefly put a load on it, you should see 12.7v.
How much voltage you see during charging will depend on your charger.
Google "12v battery state of charge" for charts that will show you the state of charge based on battery voltage.
Il Carriaggio — 1975 Argosy 24 | Il Progetto — 1976 Argosy 28 Center Bath | WBCCI# 15566
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