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Alimony Calculator

Estimate monthly alimony payments, duration, and total payout based on income gap and marriage length using a generic 30% income-difference model.

Updated July 2026 · Editorial standards

Estimated monthly alimony
$2,000/mo
Duration
6 yrs
Total estimated payout
$144,000
Income difference$80,000Annual alimony$24,000Lower earner new monthly$5,333

Income & Marriage Details

$
$
yrs

Key figures

Est. Monthly Alimony
$2,000
Duration
6 yrs
Total Estimated Payout
$144,000
Lower Earner New Monthly
$5,333

Based on a $80,000 income gap and 12 years of marriage, estimated rehabilitative alimony is $2,000/month for 6 years — a total of $144,000.The lower earner's effective monthly income rises from $3,333 to $5,333 with support. This estimate uses a generic 30% of income difference model — actual awards vary significantly by state and judge.

Est. monthly alimony
$2,000/mo
By KalkWiseVerified against official sources Updated July 2026

What is the alimony calculator — estimate spousal support?

In short

With a $120,000 vs. $40,000 income gap over a 12-year marriage, estimated rehabilitative alimony is $2,000/month for 6 years — a $144,000 total payout. The lower earner's effective monthly income rises from $3,333 to $5,333 during the support period. Actual awards vary significantly by state.

This calculator estimates monthly alimony (spousal support) payments, duration, and total payout based on the income difference between spouses and the length of the marriage. It uses a generic 30% of gross income difference model — the most common judicial benchmark — across three support types: temporary, rehabilitative (most common), and permanent.

How to use this calculator

  1. 1Enter the higher and lower earner's annual gross income
  2. 2Enter the number of years married
  3. 3Select the alimony type (rehabilitative is most common for mid-length marriages)
  4. 4Review the estimated monthly payment, duration, and total payout

The formula

monthly=(Ihigh−Ilow)×0.30÷12
total=monthly×12×n
Annual alimony = (higher income − lower income) × 30%. Monthly = annual / 12. Duration: temporary = 25% of marriage length, rehabilitative = 50%, permanent = full marriage length. Total payout = annual amount × duration years.
D
— Income difference (higher − lower earner annual gross)
0.30
— Judicial benchmark: 30% of income difference
n
— Payment duration (years of marriage × 0.5 for rehabilitative)

Worked example

The scenario

$120,000 vs. $40,000 incomes, 12 years married, rehabilitative alimony.

gives

The result

Income gap: $80,000. Annual alimony: $80,000 × 30% = $24,000. Monthly: $2,000. Duration: 12 × 0.5 = 6 years. Total: $24,000 × 6 = $144,000.

Common use cases

  • Pre-divorce financial planning to understand potential obligations
  • Comparing lump-sum settlement vs. ongoing monthly payments
  • Modeling the impact of income changes on support obligations
  • Understanding the difference between rehabilitative and permanent alimony

Limitations & assumptions

  • Uses a simplified 30% generic model — actual awards vary widely by state, judge, and individual circumstances
  • Does not account for state-specific factors: length of marriage thresholds, standard of living during marriage, or fault grounds
  • Does not model tax implications (alimony is not deductible for divorces finalized after Dec 31, 2018)
  • Legal advice from a family law attorney is essential — this calculator provides estimates only

Frequently asked questions

For a 10-year marriage, rehabilitative alimony typically lasts 4–5 years (roughly half the marriage length). Some states have duration guidelines: California courts often award alimony for half the marriage length for marriages under 10 years; over 10 years may result in open-ended orders.

Disclaimer: KalkWise calculators are provided for general informational and educational purposes only and do not constitute financial, investment, tax, or legal advice. Results are estimates based on the figures you enter and the assumptions described above. Actual outcomes will vary. Consult a qualified professional before making financial decisions.