The Short Answer
Note: Oklahoma family law can change through new legislation. Before relying on any recent or pending statutory change, confirm the effective date and final text with an Oklahoma family law attorney.
Run Your Numbers
Enter both parents’ gross monthly incomes, the number of children, and the overnight split. The calculator uses the exact statutory schedule and the same rules as the official worksheet — including the 121-overnight adjustment and the offset that decides which parent actually pays.
Oklahoma Child Support Calculator
Estimate a guideline child support amount under Oklahoma’s Income Shares model (43 O.S. §§ 118–119), including the shared-parenting adjustment for 121+ overnights. It uses the exact statutory schedule from the official OKDHS calculator workbook and determines which parent pays from the guideline logic — incomes and overnights — not a manual selection. Estimates only; see the disclaimer with your result.
Father: 80 · Mother: 285 · Total: 365 ✓
At 121+ overnights for the noncustodial parent, Oklahoma applies a shared-parenting adjustment (43 O.S. § 118E). 182–183 nights ≈ 50/50.
This is an estimate, not legal advice and not a substitute for the official DHS worksheet. It does not account for the self-support reserve at low incomes, support for other children, imputed income, or court-ordered deviations. Using this calculator does not create an attorney-client relationship with Dads.Law.
Prefer to see the math worked by hand? Our guide to how Oklahoma child support is calculated walks three real scenarios — standard, the 121-night threshold, and true 50/50 — dollar by dollar.
Oklahoma Child Support
Modification
Child support is not automatically updated as
circumstances change. To modify an existing order, you must file a
motion with the court and demonstrate a material change in
circumstances — typically a 15% or greater change in the
calculated obligation, a 36-month passage since the last order, or a
significant change in income, parenting time, or the child’s needs under
43 O.S. § 118I.
Key rule: Oklahoma courts will not retroactively
reduce child support to a date before a modification motion is filed. If
you lose your job or your income drops, file immediately. Ward v.
Ward, 1995 OK CIV APP 51, 895 P.2d 749; 43 O.S. §
118I(B)(1).
Incarceration exception: Under the 2021 revision to
43 O.S. § 118I(E), there is a rebuttable presumption
that an obligor incarcerated for 180 or more consecutive days is unable
to pay. The obligation is automatically abated — but this presumption
does not apply if the incarceration is for failure to pay child support
or for crimes against the obligee or child.
Frequently Asked Questions
Q: Does Oklahoma child support consider both parents’
incomes? Yes. Under the Income Shares model in 43 O.S. § 118,
both parents’ gross monthly incomes are combined. The mother’s income
reduces your obligation.
Q: Can child support be zero if both parents earn the same
and share equal time? Potentially, but not automatically. When
two parents share 182 overnights and earn identical incomes, the
mathematical offset can net to zero. However, add-on costs like health
insurance and childcare are still divided proportionally and are not
zeroed out by the parenting-time adjustment.
Q: What if I am self-employed? Self-employment
income is defined in 43 O.S. § 118B(E)(1) and includes all revenue from
self-employment. Courts typically scrutinize self-employment income
carefully, and a history of tax returns is generally required.
Q: Does overtime count as income? Yes. All gross
income from any source counts unless specifically excluded by statute.
Courts may average overtime over prior years if it is irregular.
Q: Can the parties agree to a different support
amount? Yes, under 43 O.S. § 118H(B), but only if approved by
the court as in the best interests of the child. Per the Oklahoma
Supreme Court in Parham v. Parham, 2010 OK 24, 236 P.3d 74, no
agreement is binding unless the court approves it.
Q: What happens to child support if I lose my job?
File a motion to modify immediately. Courts will not retroactively
reduce support to before the motion is filed. Under 43 O.S. § 118I, a
change in income can constitute a material change warranting
modification.
Q: Is the DHS online calculator the only option? The
DHS Child Support Computation Form (Excel or fillable PDF) is the
official legal document. Third-party calculators are for estimation only
and have no legal weight.
Related Guides for Oklahoma Fathers
Keep going: how 50/50 custody affects child support, when child support legally ends in Oklahoma, the step-by-step worksheet walkthrough, and our child support attorneys in Tulsa and Oklahoma City.
Sources and Legal Citations
- Oklahoma Family Law Handbook (2025–2026 ed.), Chapter 6: Child
Support, pp. 546–633 (Income Shares model: pp. 555–557; Guidelines are
not optional: p. 558; Gross income definition: pp. 557–558;
Modification: pp. 593+; Termination: pp. 624+) - Oklahoma
Statutes, Title 43 §§ 118–120 (Child Support Guidelines) - 43 O.S.
§ 118B — Income definition - 43 O.S.
§ 118E — Parenting time adjustment - 43 O.S.
§ 118I — Modification of child support - Official
Oklahoma DHS Child Support Computation Page - Official
DHS Child Support Computation Excel Worksheet (download) - Carr v. Carr, 1992 OK 106, ¶ 10, 834 P.2d 970, 973
- Hogue v. Hogue, 2008 OK CIV APP 63, 190 P.3d 1177
- Parham v. Parham, 2010 OK 24, 236 P.3d 74
- SB
1452 (2026) — Rebuttable presumption of joint custody - SB 1453
(2026) — Child support amendments