Worked example: Alimony Child Support in Brazil

Example inputs

Run this scenario in DocketMath using the Alimony Child Support calculator.

Below is a worked example showing how DocketMath calculates alimony and child support components in Brazil using jurisdiction-aware rules (jurisdiction: BR). This walkthrough is designed to be practical—so you can see exactly which inputs drive the result and how changes ripple through the output.

Scenario

Assume a parent with a salaried income and a separate household support need for one minor child.

Inputs used in this example (BR)

You can mirror these values in DocketMath’s /tools/alimony-child-support calculator:

• Jurisdiction: Brazil (BR)
• Number of children: 1
• Child age: 8
• Alimony / spousal support: Included as a distinct component (yes)
• Spousal support basis: “Income gap” style assumption (used for modeling only in the tool)
• Obligor (paying parent) monthly gross income: R$ 9,000
• Obligee (receiving parent) monthly gross income: R$ 3,000
• Other dependents in obligor household: 0
• Health or extraordinary child expenses: R$ 150/month (entered as an add-on for modeling)
• Payment frequency: Monthly

How to think about these inputs

Use this checklist before running the calculator:

If you later want to compare “with” vs. “without” health expenses, keep all other inputs fixed and change only that R$ value.

Example run

Run this scenario in DocketMath using /tools/alimony-child-support (Primary CTA): /tools/alimony-child-support.

Run the Alimony Child Support calculator using the example inputs above. Review the breakdown for intermediate steps (segments, adjustments, or rate changes) so you can see how each input moves the output. Save the result for reference and compare it to your actual scenario.

Step-by-step (what the calculator is doing)

Although the tool performs the calculations for you, you’ll get the most value by understanding the structure:

1. Compute a modeled support base from the paying parent’s income.
2. Allocate a child-support portion based on:

   • number of children (1 here),
   • the child’s age (8),
   • and any entered extraordinary expenses (R$ 150).
3. Compute a modeled alimony/spousal support portion based on:

   • the income gap between the parties (R$ 9,000 vs. R$ 3,000),
   • and whether the scenario includes a spousal-support component.
4. Output consolidated monthly amounts, typically broken into:

   • child support
   • alimony/spousal support
   • extraordinary expense add-ons (if entered)

Example output (modeled numbers)

For this walkthrough, the calculator returns a modeled monthly payment split into components like the following (illustrative of the tool’s structure):

So, under these inputs, DocketMath’s worked example would be:

• Child support subtotal: R$ 1,770/month
• Alimony/spousal support: R$ 720/month
• Estimated combined monthly payment: R$ 2,490/month

Record-keeping tip (practical)

If you’re using this to prepare a negotiation brief or a document package, keep a small audit trail:

• Income inputs (with pay stubs / tax statements as your source)
• Child’s age / school or health expense receipts
• A one-page summary of what you changed between runs (e.g., “Adjusted extraordinary expenses from R$ 150 to R$ 0”)

This makes it much easier to justify scenario comparisons—especially when you’re iterating.

Sensitivity check

Now let’s test how stable the result is. A strong way to use DocketMath is to do “one change at a time” comparisons.

To test sensitivity, change one high-impact input (like the rate, start date, or cap) and rerun the calculation. Compare the outputs side by side so you can see how small input shifts affect the result.

Baseline vs. altered scenarios

Start from the baseline:

• Paying parent: R$ 9,000/month
• Receiving parent: R$ 3,000/month
• Child: 8 years old, 1 child
• Extraordinary expenses: R$ 150/month
• Alimony component: included

Scenario A: Remove extraordinary child expenses

Change only extraordinary expenses from R$ 150 to R$ 0.

• Expected effect:

  • Child support decreases by the add-on amount
  • Alimony/spousal support typically remains unchanged (because it’s modeled from income gap and whether alimony is included)

Modeled impact (typical):

• Child support subtotal drops by R$ 150
• Total monthly obligation drops by R$ 150
• New total: R$ 2,340/month (2,490 − 150)

Scenario B: Receiving parent income increases

Change only the receiving parent income from R$ 3,000 to R$ 4,500 (a smaller income gap).

• Expected effect:

  • Alimony/spousal support (modeled from income gap) tends to decrease
  • Child support may shift slightly depending on the tool’s rules, but the most visible change is usually in the alimony component

Modeled impact (typical direction):

• Alimony decreases; child support often changes less
• New total: lower than R$ 2,490/month

Scenario C: Child is older (age adjustment)

Change only the child age from 8 to 13.

• Expected effect:

  • The child-support portion can increase when age is higher (as the tool models age-related needs)
  • Extraordinary expenses stays at R$ 150, so that portion remains constant

Modeled impact (typical direction):

• Child support subtotal increases
• New total: higher than R$ 2,490/month

What to look for in the tool output

When you compare runs, focus on these items:

Quick comparison checklist

Use this table to plan your sensitivity runs:

Related reading

• Alimony & Child Support Estimator Guide for Alabama
• Alimony & Child Support Estimator Guide for Arizona
• Alimony & Child Support Estimator Guide for Colorado