A number is only useful when its assumptions are visible.

What we calculate

Our default scenario is a full-year tax resident earning ordinary employment income from one employer. The engine subtracts a standard personal allowance, applies marginal bands progressively, adds common employee-side mandatory contributions and any selected regional estimate, then reports net pay.

Employer payroll contributions are calculated separately. They increase employer cost but do not come out of contractual gross salary.

Detailed and standard models

Global breadth and local precision are not the same thing. We use two visible model labels:

Detailed model

Jurisdiction-specific bands, allowances and major payroll contributions reviewed against primary authority material. Detailed does not mean return-ready: credits, household rules and unusual income can still be excluded.

Standard estimate

A screening model calibrated to the country’s progressive or flat-rate structure, top rate, typical allowance scale and employee contribution burden. Use it to shortlist and compare, then verify locally.

There are currently 18 detailed models and 96 standard models. We prefer an honest label over false decimal-place precision.

Progressive tax bands

Each rate applies only to the slice of taxable income inside its band. Moving into a higher band does not cause all prior income to be taxed at the higher rate. The calculator exposes the band-by-band arithmetic inside each result card.

Formula-based systems, credits and tapered allowances may require a model-specific adjustment. Country pages disclose those approximations.

Currency conversion

For an international comparison, the engine converts gross income from the selected input currency into each country’s local currency. It applies local thresholds there, and only then converts results back to the comparison currency.

Our planning exchange-rate table is dated 4 September 2026. Rates move continuously; they affect comparative presentation, not the local tax arithmetic.

Purchasing power

Purchasing-power-adjusted net income divides local take-home by a national cost index relative to the United States. It is a broad orientation tool—not an estimate of savings. It does not know your city, household, rent, school fees, healthcare choices or consumption pattern.

What we leave out

• Tax-residence determination and treaty tie-breakers
• Non-salary income, capital gains and wealth taxes
• Most credits, dependants and itemised deductions
• Municipal tax unless explicitly stated
• Benefits in kind and equity-compensation timing
• Immigration, permanent-establishment and payroll-registration analysis

Sources, updates and corrections

Detailed country pages link to primary tax authorities wherever practical and show a review month. A review date means we checked the model; it is not a guarantee that a government has made no later change.

If you find a discrepancy, include the country, tax year, input scenario, expected result and primary source in your correction note. Reproducible reports are prioritised.