Divorce alimony calculator: how courts estimate spousal support

Last updated 2026-07-09

Why isn't there one standard alimony calculator like there is for child support?

Child support has federal teeth behind it. The Child Support Enforcement Act requires every state to publish numerical guidelines, which is why every state has a formula you can actually run numbers through. ^[1] Alimony has no equivalent federal mandate. Congress left spousal support entirely to state law, so the rules in California look nothing like the rules in Alabama.

That gap matters a lot when you search for a "divorce alimony calculator." What you usually find are tools that estimate alimony based on a simple income-difference formula. Some are built by law firms as lead magnets. Others are published by state bar associations or courts. A few are genuinely useful as rough guides. Most will disclaim, somewhere in the fine print, that the result is "not legal advice" and "may not reflect what a court would order." That disclaimer exists for a reason.

A handful of states come closest to a real formula. Virginia uses a formula-based calculator for temporary support in some circuits. ^[2] Kansas publishes a "maintenance guidelines" worksheet that produces a presumptive amount. New Jersey has a long history of judges using the "one third of the difference in net income" rule of thumb, though it is not statutory. Texas caps the duration of spousal maintenance by statute and ties maximum amounts to the obligor's average monthly gross income. ^[3] Even in those states, a judge can deviate if the circumstances warrant it.

For a deeper look at how alimony works outside the calculator context, see our guide to alimony.

What factors do most states use to calculate alimony?

Most states direct their judges to weigh a list of statutory factors rather than plug numbers into a formula. The Uniform Marriage and Divorce Act, which many states borrowed from, lists considerations including the financial resources of the party seeking maintenance, the time needed for education or training, the standard of living during the marriage, the duration of the marriage, and the age and physical condition of both spouses. ^[4]

Here is how the most common factors show up across state codes:

Factor	States that explicitly include it (examples)
Length of marriage	All 50 states
Income and earning capacity of each spouse	All 50 states
Standard of living during marriage	~40 states
Age and health of each spouse	~38 states
Contributions to the other spouse's career or education	~35 states
Marital misconduct / fault	~28 states (not CA, NY, no-fault states)
Child custody arrangements	~25 states
Tax consequences	~15 states

The income gap between spouses is the single most predictable driver of whether alimony will be ordered at all. Courts look at gross income in some states, net income in others, and imputed income (what you could earn, more than what you do earn) in most. If you voluntarily reduced your income before filing, expect a judge to impute your prior earning capacity.

Marriage length drives duration more than amount. A 25-year marriage almost always produces longer support than a 5-year one. Some states tie duration directly to length: California, for instance, presumes that support for a marriage under 10 years lasts no more than half the length of the marriage. ^[5] For marriages over 10 years, California courts retain jurisdiction indefinitely, though that does not mean support lasts forever in practice.

Fault still matters in about half of states. If your state is an at-fault divorce state, marital misconduct like adultery or abandonment can reduce or eliminate alimony for the at-fault spouse. In no-fault states like California, New York (post-2010), and most others, fault is legally irrelevant to the support calculation.

How do the states with actual formulas calculate alimony?

A few jurisdictions give you something closer to a real number.

Texas caps spousal maintenance (Texas's term for court-ordered alimony) at the lesser of $5,000 per month or 20% of the obligor's average monthly gross income. ^[3] Duration caps are 5 years for marriages of 10-20 years, 7 years for marriages of 20-30 years, and 10 years for marriages over 30 years. Texas also limits who qualifies: you generally need to show a family violence conviction, a disabling condition, care of a disabled child, or a marriage of at least 10 years with insufficient resources to meet minimum needs.

Virginia circuits have circulated informal worksheets for temporary support that apply a formula roughly like: (Payor's gross income x 28%) minus (Recipient's gross income x 58%). That formula is not in the Virginia Code, it is a judicial custom in some circuits, and it explicitly does not govern final support. ^[2]

Kansas has the most formalized non-judicial process. The Kansas Maintenance Guidelines produce a presumptive monthly amount equal to 25% of the difference in the parties' gross monthly incomes, capped at 121 months of duration for marriages of various lengths. ^[6] A judge can deviate with written findings.

Michigan courts sometimes reference a formula from the Friend of the Court Bureau: roughly 25% of the payor's net income minus 50% of the recipient's net income, adjusted for specific circumstances. But Michigan's statute lists 12 factors and gives judges broad discretion, so the formula is a starting point at best.

In every case, these formulas are tools that can guide negotiation. In an uncontested divorce where both spouses agree on a support amount, a judge will usually approve any reasonable agreement without scrutinizing the math. That is one reason why having a clear, documented agreement matters more than getting the formula exactly right.

If you are working through an uncontested divorce and want to include a spousal support agreement in your paperwork, see our guide to divorce papers for what needs to be in the document.

What does a divorce alimony calculator actually output, and how accurate is it?

Most online calculators ask for gross (or net) monthly income for both spouses, marriage length, and sometimes the state. They output a monthly dollar amount and a duration. Some add fields for property division, custody, and health insurance.

The accuracy problem is structural, not a data-entry issue. A calculator cannot know whether your state imputes income, whether a judge in your county tends to deviate from guidelines, or whether your spouse's health condition qualifies for extended support under your state's statute. Nobody has published good empirical data on how well these tools predict actual court orders. The closest thing is a 2019 American Academy of Matrimonial Lawyers survey that found income disparity and marriage length were cited as the top two factors affecting support decisions, which is what the calculators mostly use, but the survey did not attempt to validate any specific tool. ^[7]

What the calculators are genuinely useful for is getting a sense of whether alimony is likely at all, roughly what order of magnitude to expect, and what to bring to a negotiation. If a calculator says $800 per month and your spouse is arguing for $2,500, you have a real number to anchor the conversation around, even if neither figure is binding.

For uncontested divorces specifically, the calculator becomes a negotiation frame rather than a court input. You and your spouse agree on an amount. You put it in your marital settlement agreement. The judge reviews it for basic fairness and signs off. That process works best when both spouses have actually done the math rather than one person guessing.

How does marriage length affect alimony duration?

Duration is the output most people underestimate when they use a calculator. Getting the monthly amount right but agreeing to the wrong duration can mean leaving tens of thousands of dollars on the table or paying far too long.

Here is how duration commonly tracks marriage length across states:

Marriage length	Typical duration range (varies by state)
Under 3 years	Rare to award; 6-12 months if ordered
3-7 years	1-3 years (rehabilitative focus)
7-15 years	30-50% of marriage length
15-20 years	50-75% of marriage length
Over 20 years	Open-ended in many states; indefinite possible

The 10-year mark is a legal threshold in multiple states. California's indefinite-jurisdiction rule kicks in. Texas's maintenance qualification threshold hits. Florida considers marriages of 17+ years to warrant a presumption toward long-term support under its 2023 statutory revisions. ^[8]

Rehabilitative alimony, the most common type ordered in short-to-medium marriages, ties duration to a specific goal: finishing a degree, completing job training, or re-entering the workforce after a period of caregiving. Courts often require the recipient to submit a rehabilitation plan showing how they will become self-supporting within the ordered period.

Permanent alimony is increasingly rare after law reforms in multiple states. Florida effectively eliminated "permanent alimony" by statute in 2023. New York, Massachusetts, and others have moved toward defined-duration models. If you are planning around permanent support, check whether your state has revised its statute in the last five years.

Does a spouse's decision to stay home with kids affect the alimony calculation?

Yes, usually significantly. A spouse who left the workforce to raise children has reduced earning capacity, which most state statutes address directly. Courts look at the length of time out of the workforce, the age at which the spouse would be re-entering, and the realistic earning capacity given current skills and market conditions.

Imputed income cuts both ways. If the stay-at-home spouse has a graduate degree and could earn $80,000 but currently earns nothing, some judges will impute a portion of that potential income into the calculation. Others will give a longer rehabilitative period instead. There is genuine inconsistency on this point even within states.

The caregiver premium also matters for duration. In states that list "contributions to the household" as a factor, years of unpaid domestic labor and foregone career advancement are treated as economic contributions to the marriage, more than personal choices. This pushes support amounts and durations higher than a raw income comparison would suggest.

If there are children still in the home, custody arrangements interact with alimony in complex ways. A parent with primary physical custody may receive higher or longer-duration support because their employment flexibility is constrained by caregiving. For how child custody intersects with financial support, see our child support calculator guide.

What is the difference between temporary and permanent alimony in a divorce?

Temporary alimony (also called pendente lite support, meaning "while the case is pending") covers the period between filing for divorce and the final decree. It maintains the financial status quo while the divorce is being processed. This is often where the Virginia-style formula is most commonly applied, because courts need a quick, defensible number.

Final alimony is what shows up in the divorce decree. It can be:

Rehabilitative: a set number of months or years to allow economic recovery. This is the most common type for marriages under 15 years.

Reimbursement: compensates a spouse who supported the other through professional school or career advancement and then divorced before sharing in the economic benefit.

Transitional: bridges a specific gap, like selling the marital home or relocating.

Long-term or indefinite: for long marriages or where a spouse has a disability or health condition that limits earning capacity permanently.

Modifiable versus non-modifiable is a separate question. Most alimony orders are modifiable if circumstances change substantially: job loss, remarriage of the recipient, serious illness. Some spouses agree in their settlement to make alimony non-modifiable, which locks both sides into the agreed amount regardless of what happens. That can make sense in a clean uncontested divorce where both parties want finality, but it is a big commitment to understand before signing.

The tax treatment changed permanently in 2019. For divorce agreements executed after December 31, 2018, alimony is no longer deductible by the payor and not taxable income to the recipient, under the Tax Cuts and Jobs Act. ^[9] Older agreements executed before that date are grandfathered under the old rules unless the parties modify them after 2018.

Can you negotiate your own alimony agreement without a judge doing the calculation?

Absolutely, and in an uncontested divorce this is exactly how it works. The parties agree on an amount and duration, put it in a written marital settlement agreement, and the judge reviews it for basic adequacy before incorporating it into the final decree. In most states, judges give substantial deference to voluntary agreements between spouses who were represented by counsel or who knowingly waived counsel.

The practical advantage of negotiating your own agreement is that you can structure it in ways a judge might not order. You could agree to a lump-sum payment instead of monthly support. You could tie increases or decreases to cost-of-living indexes. You could make it non-modifiable to give both sides certainty. A court order comes off a checklist of standard factors; a negotiated agreement can reflect what actually matters to your family.

For an uncontested divorce where alimony is agreed upon, the settlement agreement is often the most important document in the whole filing. It needs to specify the amount, the start date, the duration, the termination triggers (remarriage, death, cohabitation if you want that clause), and whether it is modifiable. Leaving any of those blank creates ambiguity that costs money to litigate later.

DivorceClear's $149 document packet includes a marital settlement agreement template built for exactly this situation, with spousal support provisions you can fill in with the terms you and your spouse have agreed on. If you want your paperwork done right from the start, that is what it is designed for.

Even in a fully agreed-upon divorce, a divorce attorney can review your settlement agreement for a flat fee. If your alimony amount is significant, that review is usually worth the cost.

How does property division interact with alimony calculations?

Courts and spouses often treat property division and alimony as substitutes for each other. A spouse who receives the house or a larger share of retirement assets may accept less monthly alimony, or none at all. A spouse who leaves the marriage with most of the liquid assets might waive support entirely.

This trade-off is explicit in many state statutes. Florida's alimony statute, for instance, directs courts to consider "the financial resources of each party, including the nonmarital and marital assets and liabilities distributed to each." ^[8] That means the property division and the alimony decision are supposed to be evaluated together.

In equitable distribution states (which is most of them), assets are divided fairly but not necessarily 50-50. The courts look at contribution to acquisition, length of marriage, and economic circumstances. A lower-earning spouse who gets a below-equal property split is more likely to receive alimony to compensate. A spouse who negotiates a larger property award has less bargaining room on alimony.

In community property states (Arizona, California, Idaho, Louisiana, Nevada, New Mexico, Texas, Washington, Wisconsin), marital property is split 50-50 by default. Alimony there is entirely separate from the property split and must stand on its own merits.

If you are working through both property division and alimony in a negotiated settlement, start with the property split and then evaluate what the income picture looks like after distribution. That sequence usually produces a more defensible and stable agreement.

What are the most reliable free alimony calculators available right now?

A few resources give you real, state-specific estimates rather than generic income-gap arithmetic.

State court self-help centers are the most credible starting point. Many states publish worksheets directly. Virginia's judicial system site includes a spousal support worksheet used by some circuits. ^[2] Kansas posts its maintenance guidelines worksheet through the state judicial branch. ^[6] California courts provide an explanation of factors on the official court help site, and many local courts offer free family law facilitator services that walk you through the calculation. ^[5]

LegalZoom and DivorceWriter both maintain state-specific alimony tools, but they are commercial products and their methodology is not publicly audited. They are useful for ballpark figures.

Support Pay and several state bar association tools (Maryland, New York) include calculators that use local judicial custom along with statutory factors.

The most important thing to understand about any free tool: they are only as good as the inputs, and none of them know your local judge's tendencies, your spouse's actual income documents, or whether your state has recently amended its alimony statute. Florida changed its alimony law significantly in 2023. ^[8] Any tool built before that change will give you wrong Florida numbers.

If you want to verify that a tool is using current law, cross-check its output against your actual state statute. Every state publishes its alimony statute in a publicly searchable code. ^[10]

When does alimony end, and what triggers termination?

Most alimony orders include built-in termination events. The most common are:

Expiration of the ordered term. The most predictable: rehabilitative and transitional support end on the agreed date.

Remarriage of the recipient. Almost universal. All 50 states terminate alimony on the recipient's remarriage unless the agreement specifically says otherwise.

Death of either party. Standard termination in all states; some agreements address whether the obligation converts to a life insurance requirement.

Cohabitation of the recipient. About 30 states allow a payor to seek termination or reduction if the recipient lives with a romantic partner in a relationship that resembles marriage. The definition of qualifying cohabitation varies significantly by state. ^[11]

Substantial change in circumstances. For modifiable orders, either party can petition the court to modify or terminate alimony if income, health, or other factors change significantly. The payor losing their job involuntarily is a classic trigger. The recipient getting a substantial raise is another.

Non-modifiable agreements eliminate the substantial-change option. If you negotiated a non-modifiable lump-sum or fixed-term agreement and your income drops dramatically, you are still obligated. That is the trade-off for certainty.

After the final divorce, alimony obligations are tracked and enforced like any other court order. Non-payment can result in wage garnishment, contempt of court, or even jail time in extreme cases. The payor does not get to unilaterally reduce payments because circumstances changed; they must petition the court.

How is alimony different in high-asset divorce cases?

The statutory factors apply in high-asset divorces the same as in ordinary ones, but the practical dynamics are very different.

In a high-asset case, maintaining the marital standard of living is a more demanding standard because the bar is higher. A lower-earning spouse who lived on $300,000 per year has a stronger argument for substantial support than someone maintaining a $50,000 lifestyle, even if the income gap percentage is similar.

Imputed income becomes more contested. A wealthy spouse's investment income, business distributions, and equity compensation all factor into the payor's income base in ways that W-2 employees do not face. Discovery in high-asset cases often centers entirely on what income is and is not includable.

High-profile divorces sometimes surface what courts actually consider in extreme circumstances. The coverage around various celebrity divorces, like the complex financial negotiations in the Nicole Kidman divorce case, illustrates how standard factors get applied when the dollar amounts are orders of magnitude larger than typical. The factors are the same; the money and the incentives are different.

For most people reading a guide like this, the high-asset frameworks are academic. What matters is whether a $1,500-per-month gap can realistically be addressed by a 36-month rehabilitative order, or whether a lump-sum buyout makes more sense for both parties. That is the practical question that an alimony calculator, used honestly as a negotiation anchor, can actually help answer.

Frequently asked questions

Is there a free alimony calculator that's actually accurate?

No free calculator is fully accurate because accuracy requires knowing your state's current statute, your local court's tendencies, and both spouses' verified income. The most reliable free resources are your state court's official self-help worksheets. Kansas and Virginia both publish official spousal support worksheets. Any commercial tool can give you a useful starting range, but treat it as a negotiation anchor, not a prediction.

How much alimony can I expect from a 10-year marriage?

A 10-year marriage sits at or near a threshold in many states. In California, 10 years triggers indefinite court jurisdiction over support. In Texas, 10 years is the minimum length to qualify for spousal maintenance. A rough estimate for most states: rehabilitative support of 3-5 years at 20-30% of the income gap. Your actual number depends on your state's factors, income difference, and whether you can reach a negotiated agreement.

Does cheating affect alimony calculations?

In about 28 states, yes. Fault-based states like North Carolina, Virginia, and Georgia can reduce or bar alimony for the at-fault spouse in cases of adultery or abandonment. In no-fault states like California and New York (post-2010), marital misconduct is legally irrelevant to the support calculation. Check your specific state statute: some states allow fault as one factor among many rather than an absolute bar.

Can alimony be calculated as a percentage of income?

Some states use percentage-based guidelines as starting points. Texas caps spousal maintenance at 20% of the obligor's average monthly gross income. Kansas guidelines use 25% of the income difference. Virginia circuits informally use a formula involving 28% of the payor's and 58% of the recipient's gross income. But even in those states, the percentage is a presumption that a judge can override with written findings.

How long does alimony last after a 20-year marriage?

A 20-year marriage typically produces long-duration or open-ended support in most states. Texas allows up to 7 years of maintenance. California courts retain indefinite jurisdiction. Florida's 2023 statute revised its long-term support rules, eliminating permanent alimony as a category. In practice, many 20-year-marriage divorces end with long-term rehabilitative or durational support rather than truly permanent orders, because courts want a defined endpoint.

Does alimony change if my spouse gets a new job after divorce?

For modifiable alimony orders, yes. If the recipient's income increases substantially, the payor can petition the court for a modification or termination. The payor must show a substantial change in circumstances, more than a small raise. Non-modifiable agreements cannot be changed regardless of income shifts. If your settlement agreement is silent on modifiability, most states default to treating alimony as modifiable.

Is alimony taxable income in 2025?

For divorce agreements executed after December 31, 2018, alimony is not taxable income to the recipient and not deductible by the payor, under the Tax Cuts and Jobs Act. Agreements executed before January 1, 2019 are grandfathered under the old rules: deductible by the payor, taxable to the recipient. Modifying a pre-2019 agreement after 2018 may trigger the new tax treatment, so get tax advice before amending any older order.

How is alimony different from child support?

Child support is paid for the benefit of the children and is calculated using state-mandated numerical guidelines. Alimony is paid from one spouse to the other and is based on discretionary factors with no federal formula requirement. Child support ends when a child reaches majority. Alimony ends based on the order's terms or termination events like remarriage. Courts treat them as entirely separate obligations, and many divorces involve both.

What happens to alimony if I lose my job?

If your alimony order is modifiable, you can petition the court for a temporary or permanent reduction based on involuntary job loss. You generally need to show the loss was not self-induced and that you are actively seeking comparable work. Courts usually require you to keep paying the full amount until a modification order is entered; you cannot unilaterally reduce payments. For non-modifiable orders, job loss does not excuse non-payment.

Can we agree on alimony without going to court?

Yes. In an uncontested divorce, you and your spouse can negotiate any alimony amount and duration you both agree to. You put it in a written marital settlement agreement, which the court reviews and incorporates into the final divorce decree. The judge rarely overrides a voluntary agreement between informed adults. This is how most uncontested divorces handle spousal support, and it gives both parties more flexibility than a litigated order.

Does alimony end when the recipient remarries?

In all 50 states, court-ordered alimony terminates on the recipient's remarriage unless the agreement explicitly says otherwise. This applies automatically in most states; you typically do not need to return to court. The payor should stop payments upon remarriage and document the date. Lump-sum alimony already paid is generally not recoverable even if the recipient remarries shortly after. Check your state's statute for whether cohabitation also triggers termination.

How do I calculate alimony in an uncontested divorce?

Start with your state's published statutory factors. Identify the income gap between both spouses' gross monthly incomes. Estimate a duration based on marriage length and the lower-earning spouse's realistic path to self-sufficiency. Use your state court's self-help worksheet if one exists. Then negotiate from that starting point. In an uncontested divorce, what you and your spouse agree on in writing is what the court will almost certainly approve.

Sources

1. U.S. Department of Health and Human Services, Office of Child Support Services: Federal Child Support Guidelines Requirements: Federal law requires every state to publish numerical child support guidelines; no equivalent federal mandate exists for alimony.
2. Virginia Judicial System, Self-Help Resources for Family Law: Virginia circuits use an informal spousal support worksheet for temporary support calculations; it is not codified in the Virginia Code.
3. Texas Family Code Section 8.055, Spousal Maintenance Limits: Texas caps spousal maintenance at the lesser of $5,000 per month or 20% of the obligor's average monthly gross income, with duration limits by marriage length.
4. Uniform Law Commission, Uniform Marriage and Divorce Act: The Uniform Marriage and Divorce Act lists maintenance factors including financial resources, education/training time, marital standard of living, marriage duration, and age and condition of both spouses.
5. California Courts Self-Help Center, Spousal or Partner Support: California presumes support for marriages under 10 years lasts no more than half the marriage length; for marriages over 10 years, courts retain indefinite jurisdiction over support.
6. Kansas Judicial Branch, Kansas Maintenance Guidelines: Kansas Maintenance Guidelines produce a presumptive monthly amount of 25% of the difference in the parties' gross monthly incomes, capped at 121 months.
7. American Academy of Matrimonial Lawyers, Survey on Alimony Factors (2019): AAML survey found income disparity and marriage length were cited as the top two factors affecting spousal support decisions by matrimonial lawyers.
8. Florida Statutes Section 61.08, Alimony (2023 revision): Florida's 2023 alimony statute eliminated permanent alimony as a category, revised long-term support rules, and directs courts to consider financial resources of each party including distributed assets.
9. IRS Publication 504, Divorced or Separated Individuals (Tax Cuts and Jobs Act alimony rules): For divorce agreements executed after December 31, 2018, alimony is not deductible by the payor and not taxable income to the recipient under the Tax Cuts and Jobs Act.
10. Cornell Law School Legal Information Institute, Alimony (state law overview): Every state publishes its alimony statute in a publicly searchable code; state statutory factors govern judicial discretion in support determinations.
11. National Conference of State Legislatures, Spousal Support and Cohabitation Laws: Approximately 30 states allow a payor to seek termination or reduction of alimony if the recipient cohabits with a romantic partner in a relationship that resembles marriage.