How We Calculate Everything
Every number on this site comes from a documented formula with a public data source. No black boxes. If we got something wrong, you can check our work.
Updated May 2026· By Net Life Value Editorial
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Net Life Value (NLV)
Net Life Value (NLV) is a composite score from 0 to 100 that measures how well you can live in a given country or city at a specific salary. It combines two equally-weighted pillars — Economic Power (purchasing-power-adjusted net income) and Quality of Life (safety, healthcare, climate, internet, cost) — using a geometric mean, the same methodology used by the UN Human Development Index. All data comes from official government sources: World Bank, WHO, OECD, and 30 national tax authorities. No AI-generated numbers are used for any quantitative data.
NLV answers one question: “Where does your salary buy you the best life?”
It's a single score from 0 to 100 that combines three things: how much money you actually keep after taxes (adjusted for local prices), how good daily life is (safety, healthcare, climate, internet), and how realistic it is to move there (visas, language, community).
NLV is personalized to your salary. The same country can score 70 at $50K and 55 at $200K, because taxes, purchasing power, and the economic cap interact differently at each income level.
NLV Formula & Geometric Mean
Two pillar scores (each 0–100) are combined using a geometric mean— the same aggregation principle the UN uses for the Human Development Index. Equal weights: 50/50.
Why geometric mean instead of a weighted average?
Looks okay, but living there would be miserable.
Punishes imbalance. You can't offset poverty with sunshine.
Why only two pillars?
Previous versions included Accessibility (visa openness, English proficiency, expat community) as a third pillar. We removed it from the score because visa requirements depend on your nationality, not the country's quality. A US passport holder and an Indian passport holder face completely different realities — a single score can't capture both. Accessibility data is still displayed alongside the NLV score as useful context.
Equal weights
What your salary is actually worth locally, after taxes and adjusted for prices. The financial reality.
Safety, healthcare, climate, internet, cost of living. What daily life actually feels like. Taxation is excluded from QoL — it's already captured in Economic Power via the tax engine.
Pillar 1: Economic Power (50%)
Economic Power scores how far your after-tax income stretches locally. A $75,000 salary yields different purchasing power in Lisbon vs London because of different tax rates and price levels. The score is capped at 100 when PPP-adjusted net monthly income reaches $8,000, based on Kahneman & Deaton's (2010) research on income and well-being.
The pipeline:
0.65 × priceLevel + 0.35 × rentRatio. Rent is ~35% of an expat's budget.The $8,000 cap
Based on Kahneman & Deaton (2010): beyond approximately $8,000/month in purchasing power, additional income has sharply diminishing returns on life satisfaction. This cap prevents ultra-low-tax countries from scoring 100 purely on tax savings at very high salaries, which wouldn't reflect real quality-of-life gains.
Pillar 2: Quality of Life (50%)
Quality of Life is the weighted average of five dimensions: Safety (25%, UNODC/IEP data), Healthcare (25%, WHO data), Cost of Living (25%, World Bank), Climate (15%, Open-Meteo bell curve centered on 22°C), and Internet (10%, ITU). Taxation is deliberately excluded from QoL to avoid double-counting with Economic Power.
Five dimensions, each scored 0–100, combined into a single QoL score using weighted averages.
Cost of Living
Price Level (50%), CPI (30%), PPP (20%)
Source: World Bank
Climate
Sunshine Hours (40%), Temperature (30%*), Precipitation (30%)
Source: Open-Meteo
Safety
Homicide Rate (50%), Global Peace Index (50%)
Source: UNODC, IEP
Healthcare
Life Expectancy (35%), Health Spending (20%), Physicians (25%), Hospital Beds (20%)
Source: WHO
Internet
Internet Users (40%), Mobile Subs (30%), Broadband (30%)
Source: ITU
* Temperature uses a bell curve, not linear scoring. See below.
Accessibility (contextual, not in score)
Accessibility measures how practical it is to relocate. It is displayed alongside the NLV score but does not affect it. Why? Because visa requirements depend on your passport, not the destination's quality. A universal score can't fairly represent this.
Visa Openness
40%Henley Passport Index score. Higher means more nationalities can enter without complex visa processes.
Source: Henley & Partners
English Proficiency
30%EF English Proficiency Index. Practical for daily life, bureaucracy, and social integration.
Source: EF Education First
Expat Community
30%Foreign-born population as % of total. Capped at 50% = score 100. Larger communities mean better infrastructure for newcomers.
Source: World Bank
Bonus: countries with an official Digital Nomad Visaprogram are flagged (but this doesn't affect the numeric score).
Tax Engine
We model each country's tax system individually. No generic “average tax rate” shortcuts. The engine handles:
- Progressive income tax brackets with country-specific thresholds
- Social security contributions (employee-side, with caps where applicable)
- Personal allowances, standard deductions, tax credits
- Country-specific logic:
- France — Quotient familial (household income splitting)
- UK — Personal allowance taper above £100K
- Netherlands — Combined tax + social insurance brackets
- Japan & Korea — Employment income deduction before brackets
- Norway — Trinnskatt (step tax) on top of flat bracket tax
- India — Surcharge + health/education cess on top of income tax
- Belgium — Municipal surcharge on top of federal tax
- Denmark — AM-bidrag (labour market contribution) before income tax
30 countries have full tax engine coverage. Sources: IRS, HMRC, DGFiP, Bundesfinanzministerium, CRA, ATO, and 24 other national tax authorities.
QoL Dimension Scoring
Each metric is normalized to 0–100 using min-max normalization:
For metrics where lower is better (homicide rate, precipitation, cost), the score is inverted. Values outside the min-max range are clamped. Missing data defaults to a neutral score of 50.
Normalization bounds
| Metric | Min | Max | Direction |
|---|---|---|---|
| Price Level | 20 | 180 | Lower is better |
| CPI | 50 | 250 | Lower is better |
| PPP | 0.5 | 15 | Lower is better |
| Temperature | n/a | n/a | Bell curve (22°C optimal) |
| Sunshine Hours | 1,000 | 3,500 h/yr | Higher is better |
| Precipitation | 200 | 2,500 mm/yr | Lower is better |
| Homicide Rate | 0 | 30 /100K | Lower is better |
| Peace Index | 1.0 | 3.5 | Lower is better |
| Life Expectancy | 55 | 85 years | Higher is better |
| Health Expenditure | 2% | 18% GDP | Higher is better |
| Physicians | 0.1 | 6 /1K | Higher is better |
| Hospital Beds | 0.5 | 13 /1K | Higher is better |
| Internet Users | 10% | 100% | Higher is better |
| Mobile Subscriptions | 30 | 180 /100 | Higher is better |
| Fixed Broadband | 0.5 | 50 /100 | Higher is better |
| Tax Revenue | 5% | 50% GDP | Lower is better |
| Corporate Tax | 0% | 40% | Lower is better |
| VAT Rate | 0% | 27% | Lower is better |
Temperature Bell Curve
Unlike other metrics, temperature is not scored linearly. Both extreme heat and extreme cold reduce quality of life. We use a Gaussian (bell curve)centered on 22°C — the midpoint of the 20–24°C range widely cited as optimal for human comfort and productivity.
This replaces the previous linear scoring (where 30°C = 100 and −5°C = 0), which unfairly rewarded extreme heat. The bell curve better reflects the reality that 28°C year-round is not more comfortable than 20°C year-round.
Real Price Index
30 everyday products priced in USD across 36 countries. We don't rely on composite indices — we track specific, identifiable products you can price-check yourself.
Product categories
Data Sources
All data comes from official government sources and international organizations. Tax brackets are sourced from 30 national tax authorities (IRS, HMRC, DGFiP, Bundesfinanzministerium, CRA, ATO, NTA Japan, and 23 others). City-level cost multipliers come from 15 official statistics offices (BEA, ISTAT, INSEE, ONS, Destatis, e-Stat, INE, GUS, ABS, StatCan, TPSO, BFS, INE PT, IBGE, Stats SA). Quality of life metrics come from WHO, World Bank, OECD, UNODC, IEP, and ITU. No AI-generated numbers are used for any quantitative data. Data is refreshed quarterly via an automated pipeline with human review.
No proprietary datasets.
Tax Authorities
International Organizations
Life expectancy, physicians, hospital beds, health spending
Tax revenue, PPP, rent price indices, wages
Price levels, CPI, migration data, international comparisons
Homicide rates and crime statistics
Internet penetration, broadband, mobile subscriptions
Global Peace Index rankings
City Data — 15 Government Sources
Numbeo is used as fallback only when no official government API exists for a city.
Other Sources
Extended Data (Beyond NLV)
Five additional public datasets enrich country profiles without being part of the NLV score. They live in a separate context namespace so the NLV formula stays untouched, and any of them can be added, removed, or refreshed independently. All sources are free, official, and refreshed quarterly via scripts/refresh-context-data.mjs.
Happiness (Cantril life-ladder)
Self-reported life satisfaction on a 0-10 scale, from Gallup World Poll data. Respondents rate their current life on an imagined ladder where 0 is the worst possible and 10 is the best possible. The annual World Happiness Report publishes country rankings based on a 3-year rolling average of this score.
Source: World Happiness Report via OWID · Coverage: 178 countries, 2005-2025 · Update: Annual (March)
Income Inequality (Gini coefficient)
The Gini coefficient measures inequality in income distribution on a 0-100 scale. 0 means everyone earns exactly the same, 100 means one person earns everything. Below 30 is relatively equal (Northern Europe), 30-40 is moderate, above 50 is highly unequal (Sub-Saharan Africa, parts of Latin America). Lower is better for social cohesion.
Source: World Bank / LIS via OWID · Coverage: 171 countries, irregular updates · Note: OWID publishes as 0-1 ratio, we multiply by 100 for display
Air Quality (PM2.5)
Annual mean concentration of fine particulate matter (PM2.5) in µg/m³. PM2.5 is small enough to enter the bloodstream through the lungs. The 2021 WHO guideline is <5 µg/m³ annual exposure; above 35 µg/m³ is associated with significant cardiovascular and respiratory impact. Country-level average — large cities may differ.
Source: WHO Ambient Air Quality Database via OWID · Coverage: 196 countries · Update: Annual
Education (PISA)
Programme for International Student Assessment — standardized test scores for 15-year-olds in Math, Reading, and Science. OECD administers it in ~80 countries every 3 years. Scores cluster around 500 (OECD average), top countries (Singapore, Estonia, South Korea) score 540+, struggling ones below 400. The most relevant relocation metric for families with school-age children.
Source: OECD PISA via OWID · Coverage: ~80 countries · Update: Every 3 years (last: 2022, next: 2025)
Human Development Index (HDI)
UNDP's composite index combining life expectancy at birth, expected years of schooling, and gross national income per capita. Scored 0 to 1, where 1 is maximum human development. Above 0.8 = very high, 0.7-0.8 = high, below 0.55 = low. It's the most widely-cited composite measure of national development beyond GDP.
Source: UNDP HDR via OWID · Coverage: 189 countries, 1990-present · Update: Annual
Why separate from NLV? These metrics measure dimensions that are either subjective (happiness), irregular (Gini), not individually-relevant (PM2.5 depends on your specific city), or composite of things NLV already captures (HDI overlaps with life expectancy which is already in QoL, plus income which is in Economic Power). Mixing them into the NLV formula would either dilute or double-count. Keeping them as a parallel contextlayer gives users the full picture without breaking the NLV score's interpretability.
Limitations
Employment income only
The tax engine models salary income. Self-employment, capital gains, rental income, and dividends are not included. Special tax regimes (Portugal NHR, Netherlands 30% ruling, UAE free zones) are not modeled.
City coverage is partial
38 cities across 17 countries have city-specific cost and rent multipliers from official government statistics. Other cities inherit country-level averages. City data comes from 15 national statistics offices with Numbeo as fallback — each city page shows its exact data source.
Opinionated weights
The 50/35/15 NLV split and the QoL dimension weights reflect our editorial judgment. Different people value different things. We publish the formula so you can mentally adjust.
Point-in-time data
Exchange rates, prices, and tax brackets are snapshots, not live feeds. Data is refreshed periodically. Always verify current rates before making financial decisions.
Climate is averaged
Avg temperature and sunshine hours are annual averages. A country with mild winters and hot summers might average 18°C but feel very different from one that's 18°C year-round.
Accessibility is simplified
Visa openness is modeled at the country level, not by nationality. A US citizen and an Indian citizen face very different visa requirements — our score doesn't capture this yet.
Questions about the methodology? Found an error? The entire codebase, including all scoring functions, is deterministic and can be traced from the JSON data files through the calculation functions to the rendered output. No machine learning, no opaque models — just arithmetic.