Fairsum

California family law calculators (2026)

Guideline estimates for California, each built from the statute and shown step by step. Pick a calculator to start, or scan the key numbers below.

Key 2026 figures in California

Guideline formula (Child support)

Family Code section 4055. HN is the higher earner's net income, TN both parents' combined net income.

CS = K[HN - (H%)(TN)]

Two children (Child support)

Three children x 2, four x 2.3, five x 2.5, up to ten children x 2.86.

x 1.6

Add-ons (Child support)

Work-related childcare and uninsured health costs, unless the court orders an income-based split.

Split 50/50

Ends at (Child support)

Age 18, or 19 if the child is still a full-time high school student living at home.

18 or 19

Temporary formula (Alimony)

40% of the higher earner's net income minus 50% of the lower earner's, in most counties.

40% minus 50%

Long-term support (Alimony)

No formula after judgment; the court weighs need, ability to pay, the marital standard of living and 12 other factors.

Section 4320 factors

Marriage under 10 years (Alimony)

A common yardstick for how long support continues.

About half the length

Marriage of 10+ years (Alimony)

The court keeps power to order support, though the amount is expected to step down over time.

Indefinite jurisdiction