Quick answer
Eligibility, amount, duration, and calculation depend on local law and the facts; marriage alone does not establish a fixed payment.
Do now
Gather income, employment history, household expenses, health information relevant to earning capacity, and the marriage timeline. Ask about temporary support and what must be requested before judgment.
Local note
NY often uses the term “maintenance.” DC court guidance specifically cautions about requesting alimony in the divorce case. Do not use a calculator as a final legal determination.
Official sources
NJ Courts — Divorce, NY Courts — Divorce frequently asked questions, DC Courts — Divorce.