California calculates temporary and long-term spousal support differently.

For temporary spousal support, many courts use a local guideline formula. A commonly used starting point is 40% of the higher earner's net monthly income minus 50% of the lower earner's net monthly income. The calculation may be adjusted for taxes, child support and child-related expenses. The formula used can vary by county, and a judge is not required to order the exact result shown by a calculator. The California Courts Self-Help Guide explains the purpose of temporary support and how to request it.

For long-term spousal support, there is no statewide mathematical formula. The judge must weigh all relevant factors under California Family Code § 4320 before deciding whether support should be ordered, how much should be paid and how long it should continue.

Temporary spousal support may help one spouse cover expenses while a divorce or legal separation is pending. Courts often use local income-based guidelines to estimate the amount.

Long-term spousal support, sometimes called post-judgment or permanent support, may begin when the divorce is finalized. “Permanent” does not necessarily mean support will last forever. The judge decides the amount and duration after reviewing the marriage and each spouse's circumstances under California law. The California Courts guide to long-term spousal support provides additional information.

There is no automatic payment period. For a marriage of less than 10 years, California law generally sets a goal that the supported spouse become self-supporting within a reasonable time, often described as one-half the length of the marriage. This is a goal, not a hard deadline, and the judge may order a shorter or longer period.

For a marriage of 10 years or more, the court generally keeps the power to address spousal support unless the spouses agree otherwise in writing or the court ends that authority. A long marriage does not guarantee lifetime alimony.

Under California Family Code § 4336, a marriage lasting 10 years or more is presumed to be a marriage of long duration for purposes of the court retaining jurisdiction over spousal support.

The 10-year mark does not create an automatic right to alimony, set the payment amount or guarantee support for life. It generally means the court may keep the authority to make or change support orders after the divorce, depending on the judgment and any agreement between the spouses. A court may also find that a marriage lasting less than 10 years was a marriage of long duration in some circumstances.

Temporary-support calculations generally begin with each spouse's net disposable income, not simply gross salary. Depending on the circumstances, the financial information considered may include:

• Wages and salary
• Overtime
• Bonuses and commissions
• Self-employment or business income
• Rental income
• Investment income
• Stock compensation
• Retirement income
• Other recurring income

Taxes, health insurance, mandatory retirement contributions and other allowable deductions can affect net income. Irregular earnings or a privately owned business may require a closer review than an online calculator can provide.

For divorce or separation instruments executed on or after January 1, 2026, alimony payments are generally not deductible by the payer and not treated as taxable income to the recipient for either federal or California income-tax purposes.

Different rules may apply to older agreements. The California Franchise Tax Board's alimony guidance explains the treatment of agreements executed before 2026 and later modifications. Because taxes can depend on the date and language of an order or agreement, consider speaking with a tax professional about your specific situation.

Sometimes. Unless an order or agreement makes support nonmodifiable, a court may change or end spousal support after a material change in circumstances, such as a major change in income, job loss, retirement or reduced financial need. Courts usually cannot change amounts that became due before a request to modify was filed, so timing matters.

Support generally ends when either spouse dies or the supported spouse remarries, unless the spouses agreed otherwise in writing. Cohabitation does not automatically end support, but it creates a rebuttable presumption of reduced need that may support a request to modify or terminate the order.

This calculator can provide a useful estimate of temporary support when the information entered is accurate and the court uses a similar guideline. It cannot predict exactly what a judge will order.

California counties may use different temporary-support methods, and a judge can reach a different result. The calculator also does not determine long-term support because that decision requires a review of the California Family Code § 4320 factors. Use the number to prepare a budget, compare possible outcomes and identify questions to ask before making financial decisions.