Where HEADING's numbers come from

Tax & take-home

• Marginal income-tax brackets and employee social-security rates from the OECD Tax Database, PwC Worldwide Tax Summaries, and national revenue authorities (e.g. IRS, Belastingdienst, HMRC, Agencia Tributaria).
• Each country entry stores the primary source URL and is refreshed on a quarterly cycle.
• Special expat regimes — the Netherlands 30% ruling, Portugal NHR/IFICI, and Spain's Beckham Law — are modelled from their published rules.

Cost of living

• AI-assisted research (Anthropic's Claude with web search) compiles public-source data per city: housing (rent and buy), transport, utilities, groceries and dining, healthcare, schooling, and quality-of-life indicators.
• Results are cached per city and refreshed on tiered cycles — economics/salaries ~90 days, lifestyle ~150 days, and ~30 days for volatile economies (high-inflation/FX markets).
• Each city record carries an “as-of” date so you can see how current the underlying data is.

Salaries

• Domain- and seniority-specific salary benchmarks drawn from public salary datasets and market data, so the comparison reflects what someone in your role and level would realistically earn locally.

How we turn sources into a number

• We combine your inputs (household, role, income, housing, priorities) with the city data to compute a household-level true monthly cost, estimated take-home pay, and a relative “financial freedom” comparison across cities.
• The model is comparative and illustrative — it's designed to frame your own research, not to replace a tax or financial professional.

What this is — and isn't

• Estimates, not advice. Figures are approximations from third-party data of varying freshness and will differ from your actual results.
• Not a live feed. Data is researched and cached, then refreshed on the cycles above.
• Your inputs are never sold or shared. See our privacy policy for how we handle and delete data.
• We don't claim precision — we aim for an honest, personalised estimate.