Is the Texas OAG child support calculator accurate? The current one is. An old copy still online is not.

This post explains how the Texas child support guideline computes a number. It is not legal advice, it is not a substitute for the advice of an attorney, and it does not tell you what a court will order in your case. Texas judges retain discretion under Tex. Fam. Code §154.123 to vary from the guideline when the evidence rebuts the guideline presumption, and the facts that drive a real order (income characterization, medical support, multiple households, enforcement history) are case-specific. Talk to a Texas family lawyer about your situation. What follows is arithmetic and statute, which is a different thing from advice.

Correction, 2026-10-08: an earlier version of this post said the OAG’s online calculator still applied the superseded $9,200 cap. That was wrong. Our check had been reading a legacy copy of the tool. The calculator the OAG links to today applies $11,700, and an archived capture shows it already did by May 2026. We have rewritten the post and fixed our probe.

With that said: the Office of the Attorney General’s current online child support calculator, the one linked from texasattorneygeneral.gov, applies the $11,700 cap on monthly net resources that took effect on September 1, 2025. An older version of the same tool, still live at a /v1 address, applies the superseded $9,200 cap. We checked both directly on 2026-10-08.

For most cases the difference between those two pages makes no difference at all. For cases at or above the cap, it changes the guideline figure. This post explains which is which, and shows the arithmetic either way.

The short version

• The statutory cap on monthly net resources is $11,700, effective 2025-09-01, under Tex. Fam. Code §154.125(a) as adjusted through the §154.125(a-1) review cycle.
• The OAG’s current calculator applies $11,700; a legacy version still online applies $9,200. We checked both on 2026-10-08 at 22:52 UTC. The current page (csapps.oag.texas.gov/monthly-child-support-calculator) loads income_cap: 11700 from its configuration. The legacy page (…/monthly-child-support-calculator/v1) still ships let $cap = 9200, alongside 2021 payroll-tax constants.
• For anyone at or above the cap, the legacy page’s figure is $500 per month lower for one child ($6,000 a year), $625 for two, $750 for three. The legacy /v1 tool understates in every one of those cases.
• This is an outdated page, not a formula error. The legacy tool’s percentages track §154.125. Its cap and its payroll-tax constants are the parts that were never updated.
• A second divergence is unrelated to the cap: “net resources” under §154.062(d) is not take-home pay, and every calculator that follows the statute applies that definition. It is covered below because it accounts for most of the confusion about Texas support figures.

The operational point: a figure produced by the legacy /v1 page reflects the 2019 cap, and the guideline output from any calculator is a starting presumption, not the order.

What the cap actually does

Texas does not use an income-shares model. California computes a single guideline figure from both parents’ incomes and the custody timeshare percentage; Texas does something structurally different and considerably simpler to state. Under §154.125(b), the guideline applies a flat percentage to the obligor’s monthly net resources, stepped by the number of children before the court:

Children before the court	Guideline percentage of net resources
1	20%
2	25%
3	30%
4	35%
5	40%
6 or more	Not less than the 5-child amount

(Below $1,000 a month in net resources, a lower schedule applies under §154.125(c): 15% for one child, rising five points per child.)

The cap is what makes this bounded. §154.125(a) applies those percentages only to net resources up to a ceiling. Above the ceiling, the guideline percentage stops applying to the excess. A parent with $9,000 a month in net resources and one child is inside the cap and the math is simply 20% of $9,000. A parent with $40,000 a month is far above it, and the guideline figure is 20% of the capped amount, not 20% of $40,000.

That ceiling is not fixed in the statute’s text. Since 2021, §154.125(a) refers to the maximum “as most recently published by the Title IV-D agency in the Texas Register,” and §154.125(a-1) directs that agency, the OAG, to adjust the amount every six years for inflation, based on the consumer price index, and to publish the adjusted figure in the Texas Register before it takes effect. The history is short:

• 2007, $7,500, the base amount then written into §154.125(a)
• 2013-09-01, $8,550, the first six-year adjustment
• 2019-09-01, $9,200, the second
• 2025-09-01, $11,700, the third, published in the Texas Register in 2025

The 2025 adjustment was large, about 27%, because it absorbed six years of CPI in a single step. That size is exactly why staleness matters. A tool lagging by one small adjustment produces a rounding-error difference. A tool lagging across a 27% step produces a materially different number for every high-earner case it touches.

The arithmetic of the divergence

Here is the computation the two caps produce, holding everything else identical. Assume an obligor whose monthly net resources are at or above $11,700: a high earner, but not an extreme one; this is a household in the low-to-mid six figures gross.

One child, 20%:

• Against the current statutory cap: 20% × $11,700 = $2,340 per month
• Against the legacy page’s $9,200 cap: 20% × $9,200 = $1,840 per month
• Difference: $500 per month, or $6,000 per year

Two children, 25%:

• Statute: 25% × $11,700 = $2,925
• Legacy page: 25% × $9,200 = $2,300
• Difference: $625 per month, $7,500 per year

Three children, 30%:

• Statute: 30% × $11,700 = $3,510
• Legacy page: 30% × $9,200 = $2,760
• Difference: $750 per month, $9,000 per year

A few things worth being precise about, because this is the part people get wrong when they repeat it.

The divergence only appears at or above $9,200. If the obligor’s net resources are $6,000 a month, both caps leave 20% of $6,000 for one child, and the cap plays no part. That is very likely why a stale copy can stay online without anyone noticing: it only bites the cases where the most money is at stake.

Above the cap, the divergence is flat, not proportional. Whether net resources are $11,700 or $117,000, the one-child understatement is the same $500 a month, because both calculations are pinned to their respective ceilings. The gap does not widen with income.

The legacy figure understates the guideline amount, in the obligor’s favor. Above the cap the gap is $6,000 a year for one child and grows with each additional child, to $12,000 a year for five.

Why an old copy of the official tool goes stale

It is worth being precise about the mechanism here, because “the state’s calculator is wrong” implies more than the facts support. The OAG did update its calculator. What it did not do is take the old one down.

The cap is not hardcoded in the statute in a way that a code update automatically propagates. §154.125(a-1) creates an administrative cycle: the OAG computes the inflation adjustment, publishes it in the Texas Register, and the new figure takes effect on September 1 of that year. The statute changes by publication. A calculator changes only if someone updates that calculator.

The current OAG tool reads its cap and tax figures from configuration, so it moved with the 2025 adjustment. The legacy /v1 page carries the same values as constants in its client-side JavaScript, and nobody edited them. A page nobody links to is precisely the kind of thing nobody maintains.

We say this as builders rather than critics, and with some humility: our own check made the same kind of mistake. It was pointed at the legacy page, and for a while it told us, accurately, that the page we were watching had not changed. It was watching the wrong page. That is also why we treat our own cap as data rather than as code. Our Texas engine stores the cap history as dated entries, so a computation is performed against the cap in effect on the date that matters, and a 2031 adjustment is a data change rather than a code change. We also run an automated daily probe against the OAG tools: it reads the cap the current calculator applies, and it records the legacy page’s value separately, labelled as legacy.

A second divergence: net resources is not net income

The cap is the narrow, checkable discrepancy. There is a second gap that is definitional rather than a maintenance lapse, and it affects every Texas case rather than only those above the cap. It is where most of the confusion about Texas support numbers actually comes from.

“Net resources” under §154.062 is a statutory construct. It is not your take-home pay. §154.062(d) enumerates what comes out of gross to get there, and the list is much shorter than the list of things actually deducted from a paycheck:

• Social Security taxes
• Federal income tax, computed under a specific presumption discussed below
• State income tax, where applicable; for Texas residents, zero
• Union dues
• The cost of the child’s health insurance, dental insurance, or cash medical support ordered by the court
• Contributions to a retirement plan that employment requires, but only for an obligor who does not pay Social Security taxes (§154.062(d)(6))

Read what is absent. 401(k) and other voluntary retirement contributions are not deducted. The narrow exception is an obligor who pays no Social Security tax: contributions to a plan required as a condition of employment come out under §154.062(d)(6). Car payments, mortgage payments, credit-card obligations, wage garnishments for other debts, and the ordinary cost of living are not deducted either. A parent contributing 15% of salary to a 401(k) has a take-home number substantially below their net resources, and the guideline runs on the larger figure.

This is the single most common source of “the calculator says I owe more than I can afford.” The calculator is not malfunctioning. It is computing a statutory quantity that was never intended to equal disposable income.

The single-filer presumption

There is one more piece of §154.062(d) that deserves its own paragraph, because it is genuinely counterintuitive and it drives the arithmetic more than most people expect.

§154.062(d)(2) requires deduction of federal income tax “based on the tax rate for a single person claiming one personal exemption and the standard deduction.”

That is a statutory presumption, not a description of the obligor. It applies regardless of actual filing status. A married obligor filing jointly with three dependents still has net resources computed as though they were a single filer taking the standard deduction. The statute fixes the assumption so the computation is uniform and administrable across cases; the cost is that it systematically diverges from anyone’s real tax liability.

The presumption also has an odd historical artifact embedded in it. It refers to “one personal exemption,” and after the 2017 Tax Cuts and Jobs Act the personal exemption’s value is zero. IRC §151(d)(5) reduced it to nothing, and 2025 federal legislation made that permanent. The statutory language still says what it says. The reconciliation in practice is the tax charts the OAG must promulgate annually under §154.061(b), which express the presumption as concrete numbers each year. Our engine computes the deduction under the same presumption.

Checking a figure against the statute

Where a figure came from the legacy /v1 page and net resources are near or above $9,200 a month, the guideline figure under the current cap differs. The statute’s arithmetic is: monthly net resources under §154.062(d), capped at $11,700, times the §154.125(b) percentage for the number of children before the court.

The authority is the statute and the Texas Register publication, not any calculator’s output, ours included. No calculator is authority in a Texas courtroom. §154.125 is authority. A calculator is a tool for arriving at the number the statute describes, and its value is entirely a function of whether it implements the statute correctly on the day it is used.

That is the reason we publish our methodology, cite the section behind every step, and show the arithmetic rather than only the result, so the figure can be checked against the statute rather than taken on trust.

Our Texas child support calculator applies the current $11,700 cap, shows each §154.062(d) deduction as a separate line, and cites the controlling subsection at every step. Where our figure and the OAG-equivalent figure diverge, we show both and explain the reason rather than quietly picking one.

Primary sources

Everything above is checkable against primary sources, and we would rather you check it than take our word:

• Tex. Fam. Code Chapter 154: the controlling chapter, at statutes.capitol.texas.gov. §154.062 defines net resources, §154.125 sets the percentages and the cap, §154.125(a-1) creates the six-year adjustment cycle, and §154.126 governs the above-cap analysis.
• The OAG’s current calculator at csapps.oag.texas.gov. The cap it applies is stated on the page. The legacy copy at the /v1 address is the one that still shows $9,200.
• The Texas Register publication of the 2025 cap adjustment, which is what made $11,700 effective on 2025-09-01.

Both OAG calculator pages checked on 2026-10-08. Statutes current as of 2026-10-08 (Texas Legislature website, current through the 89th Legislature, 2nd Called Session). If the OAG changes either page, our daily probe exists so that we notice, and we will update this post and say so.