Alimony Calculator
Estimate monthly spousal support and a suggested duration from both spouses’ incomes and the length of the marriage, using a common rule-of-thumb formula. Calculates in your browser.
Estimated monthly alimony
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Show the math
A common rule of thumb based on the income gap:
annual = 30% of payor − 20% of recipient income
capped so recipient total ≤ 40% of combined income
Generic estimate only. Alimony (spousal support) rules vary enormously by state, many use discretionary factors rather than a formula. Marriages of 20+ years often qualify for indefinite support. Consult an attorney. All math runs locally in your browser.
What this does
An alimony calculator estimates monthly spousal support and a suggested duration from both spouses’ incomes and the length of the marriage, using a common rule-of-thumb formula.
How it works
A common rule of thumb is 30% of the payor’s income minus 20% of the recipient’s, capped so the recipient’s total income stays at or below 40% of the combined income. Duration is often tied to the marriage length.
How to use it
- Enter both spouses’ incomes.
- Enter the length of the marriage.
- Read the estimated monthly support.
- See the suggested duration.
Understanding your result
This is not legally binding. Most states use discretionary factors rather than a fixed formula, so actual awards vary widely, consult an attorney.
Example
If the payor earns $8,000 and the recipient $3,000 a month, the rule of thumb suggests roughly $1,800 in support.
Sources & methodology
Last updated .
Frequently asked questions
How is alimony estimated?
A common rule of thumb is 30% of the payor’s income minus 20% of the recipient’s, capped so the recipient’s total income stays at or below 40% of the combined income.
How long does alimony last?
Many guidelines tie duration to the length of the marriage; marriages of 20+ years often qualify for long-term or indefinite support.
Is this legally binding?
No. Most states use discretionary factors rather than a fixed formula, so actual awards vary widely. Consult an attorney.
Is my data kept?
No. Everything is computed locally in your browser.
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