Methodology

Every NumberMotive calculator is designed so the formula, assumptions and limitations are visible. An estimate is not an official result, a payroll calculation or professional advice.

Formulas and assumptions

Each working calculator documents the math it uses and the assumptions that affect the result. Visitor-entered rates, hours, costs and similar inputs are planning assumptions. NumberMotive does not invent official tax rates, wage bases or legal eligibility outcomes.

Limitations

The published planning calculators produce estimates. They do not calculate taxes, deductions, benefits, bonuses or legal eligibility unless a specific tool states that a visitor-entered rate is being applied as a planning input. A calculator is not a government filing, a payroll run or a professional opinion.

Review dates and tests

Working calculators show a review date. The core formulas are covered by automated tests so a change in PHP or JavaScript can be checked against the same expected results. That testing is an engineering control. It is not an independent audit, a legal review, a certification or a government validation.

Rule versioning

When a calculator relies on an official tax or labor schedule, that schedule is versioned and dated in code instead of being invented at runtime. Planning worksheets that use only the numbers a visitor enters do not publish a legal schedule. NumberMotive does not claim government authorization for either kind of tool.