Child Support Estimator

A ballpark using the income-shares model most states apply — before the lawyer meeting

$—
Estimated Monthly
$—
Combined Basic Obligation
Your Income Share
StepAmount

Child support looks like a mystery and is mostly a lookup table: 41 states use the income-shares model — combine both parents' incomes, read the "basic obligation" from a state table (what an intact household at that income spends on kids), split it by income share, then adjust for overnights and add-ons. This estimator runs that generic math so the number at the attorney's office arrives as confirmation, not shock. It is an orientation tool, not legal advice, and never a substitute for your state's official calculator.

The Model, Step by Step

  1. Combined income: both parents' gross (some states net). Voluntary unemployment gets income imputed — quitting your job does not quit the obligation.
  2. Basic obligation: the state table's figure for that combined income and child count — roughly 17%/25%/29% of income for 1/2/3 kids, tapering at higher incomes.
  3. Add-ons: children's health-insurance premiums and work-related childcare ride on top, split proportionally — these routinely add $300–600 to the base and surprise everyone.
  4. Income share: each parent owes their percentage; the non-custodial parent's share becomes the transfer.
  5. Parenting-time credit: overnights above a threshold (often ~92/year) discount the transfer; true 50/50 with equal incomes can net near zero — which is why overnight counts are the most-litigated number in family court.

What Moves the Number (and What Doesn't)

  • Moves it: overnights across a threshold, job changes (up or down — modifications require filing, and arrears never retro-adjust), who insures the kids, new childcare, additional children in new families (varies).
  • Doesn't: the other parent's new partner's income (almost everywhere), how the money is spent (no receipts required), remarriage per se, informal side agreements (courts enforce orders, not texts — get modifications ordered).

The Practical Rules Everyone Learns Late

Pay through the state registry, not Venmo (the registry record IS your proof); file modifications the month circumstances change (arrears accrue at the old number and are nearly indestructible — they survive bankruptcy); and treat the parenting schedule as the financial document it is. Support and custody are legally separate: withholding visitation over unpaid support (or vice versa) hurts the withholder in court, every time.

How to Use the Estimator

  1. Enter both gross incomes, kids, your realistic overnight count, and the add-ons.
  2. Read the estimate and the step table — the same anatomy your state's worksheet will have.
  3. Then run your state's official calculator and bring both to the consultation.

Frequently Asked Questions

How accurate is this vs what a court orders?

It's a generic income-shares ballpark — states differ on tables, net-vs-gross, overnight formulas and caps. Expect your state's official worksheet within ±20% of this for typical cases; use this to orient, the state's to plan, and a lawyer to file.

Does 50/50 custody mean no child support?

Only with roughly equal incomes. Most states offset: each parent's obligation computed, higher earner pays the difference — so 50/50 with a 70/30 income split still transfers money. The overnight credit is large but not income-blind.

Can we just agree to a different amount?

Courts must approve deviations from guidelines (they usually accept reasonable, explained agreements — especially above-guideline ones). UNORDERED side deals are the trap: the registry keeps accruing the ordered amount as arrears regardless of your texts.

What income counts — bonuses, overtime, side gigs?

Generally yes: guidelines reach gross income from nearly all sources (bonuses, commissions, rental income, recurring overtime). Fluctuating income usually gets averaged; hiding it gets found in discovery and remembered by judges.

When can the amount be changed?

On 'substantial change in circumstances' — commonly ±15-20% income shifts, job loss, custody changes, new health needs. File IMMEDIATELY: modifications run from the filing date, never earlier, and informal forbearance doesn't stop arrears.

How long does support last?

Age 18-to-21 by state (often 'or high school graduation'), longer for disabled adult children; college contribution is ordered in some states and negotiable everywhere. Arrears outlive the child's majority — they're collectible for decades.

Is my information private?

Yes — every figure computes locally in your browser and is never transmitted.

Run the generic math here, the official worksheet next, and file — never handshake — every change. Support is a table lookup wearing a courtroom; the parents who treat it as arithmetic spend less on lawyers and less on each other's nerves.

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