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
The American Academy of Matrimonial Lawyers' recommended formula (2008), based on the income gap:
annual = 30% of payor − 20% of recipient income
capped so recipient total ≤ 40% of combined income
duration = marriage length × 0.3 (0–3 years), 0.5 (3–10), 0.75 (10–20); over 20 years: permanent
Generic estimate only. Alimony (spousal support) rules vary enormously by state, many use discretionary factors rather than a formula. The AAML formula is a guideline, not law in any state. 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
The American Academy of Matrimonial Lawyers recommends 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 the marriage length times 0.3 (up to 3 years), 0.5 (3–10), or 0.75 (10–20), and permanent after 20 years.
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 $96,000 and the recipient $36,000 a year ($8,000 and $3,000 a month), 30% minus 20% gives $1,800 a month, but the cap keeps the recipient at 40% of the $11,000 combined monthly income, so support is limited to $1,400 a month.
Sources & methodology
- Kisthardt, Re-thinking Alimony: The AAML’s Considerations for Calculating Alimony, 21 J. Am. Acad. Matrim. Law. 61 (2008), AAML recommended amount and duration factors
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?
Under the AAML guideline, duration is the length of the marriage times 0.3 for marriages up to 3 years, 0.5 for 3–10 years, and 0.75 for 10–20 years; marriages over 20 years suggest permanent support. An 8-year marriage suggests 4 years; a 15-year marriage, 11.25 years.
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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