How Relocation by Numbers Works

These calculators are built to compare how a move could change take-home pay, monthly housing pressure, cost of living, relocation readiness, and long-term FIRE timelines across different cities, states, and international destinations.

The goal is to help answer practical planning questions such as:

• How might my monthly budget change if I move?
• How much salary would feel equivalent in another location?
• Would a lower-cost move improve my monthly flexibility?
• How might relocation change my FIRE timeline?
• How much cash do I likely need before an international move?

Relocation by Numbers estimates after-tax income using a simplified planning model that may include federal income tax, FICA payroll taxes, filing status, optional retirement contributions, and state-level or country-level income tax assumptions where applicable.

Tax handling varies by jurisdiction. Some states or countries have no income tax, some use flat-rate logic, and others use simplified bracket-based estimates. These calculations are designed to support comparison, not to produce a filing-ready tax result.

Tax calculations do not attempt to fully model every real-world variable. Depending on the tool, they may not fully account for itemized deductions, credits, local taxes, self-employment rules, investment income treatment, treaty treatment, residency edge cases, or unusual filing situations.

The U.S. calculators use 2026 tax rules taken from government sources (the IRS, state tax agencies and legislatures, and city or county governments), last checked October 13, 2026. They estimate the tax owed for the year on wages for a resident with the standard deduction. They do not estimate paycheck withholding, which follows different employer formulas.

Housing estimates are one of the largest parts of the model because housing is often the biggest recurring expense in a move. Depending on the calculator, users may compare renting or buying and estimate how much of their take-home pay may go toward housing.

Buy-mode estimates may include mortgage principal and interest, property taxes, homeowners insurance, HOA costs, and PMI when down payment assumptions suggest PMI may apply. Rent-mode estimates may include monthly rent and renter-related housing costs where relevant.

City rent, home-price and property-tax defaults come from the U.S. Census Bureau American Community Survey 2020-2024 (5-year estimates). Rent is what households that moved in during 2023 or later pay, converted to the contract-rent basis (tables B25113, B25058 and B25064); home price is the owner-reported value of homes bought in 2023 or later (B25109). Where that group is too small to be reliable (margin of error above 25% of the estimate), the all-renter or all-owner median is used instead, and the city page says which. The property-tax rate is median real estate taxes paid divided by median home value (B25103 and B25077); a city without its own figure uses its state's.

These housing calculations are designed for planning comparison only and do not represent a mortgage approval, underwriting decision, or final lender quote.

Cost-of-living comparisons use location-specific assumptions for categories such as housing, groceries, utilities, transportation, healthcare, and other recurring living expenses when those inputs are available in the model.

City price levels come from the Bureau of Economic Analysis Regional Price Parities for 2024, which compare a metro area (or the state, for cities outside a metro area) with the national average of 1.00. Housing uses the housing index and utilities the utilities index. BEA does not publish separate indexes for groceries, transportation or healthcare, so groceries and transportation use the goods index and healthcare uses the other-services index.

The national dollar budgets those indexes scale (groceries, utilities, transportation, healthcare, childcare and miscellaneous), plus insurance, closing costs and state sales tax, are planning assumptions rather than government figures.

In some parts of the site, weighted category comparisons are used so the model reflects the fact that housing usually matters more than smaller spending categories. In other parts of the site, the comparison may rely more heavily on rent-based logic, city-level defaults, or broader affordability heuristics when a full category-level model is not available.

These estimates should be treated as directional planning inputs. Actual living costs vary by neighborhood, household size, commute, lifestyle, insurance choices, and personal spending habits.

International tools add another layer beyond domestic relocation because visa path, residency status, one-time setup costs, and country-specific tax treatment often matter as much as monthly living costs.

Depending on the destination and tool, international relocation estimates may include destination-city rent and essentials, one-time moving costs, visa or permit fee assumptions, healthcare-related costs, and country-level tax treatment for planning purposes.

These tools do not fully model every immigration path, residency rule, employer sponsorship structure, treaty rule, or local legal edge case. They are intended to help users compare scenarios before pursuing official visa or tax guidance.

FIRE estimates are based on a planning framework that may include annual spending, withdrawal rate, after-tax income, savings assumptions, investment growth assumptions, inflation assumptions, and current portfolio values.

The FIRE number is generally estimated from annual spending divided by the selected withdrawal rate. The timeline to financial independence depends on contributions, current assets, growth assumptions, inflation assumptions, and location-adjusted spending.

Location matters because taxes and spending can both change when you move. A lower-tax state or lower-cost city may reduce the income needed to support your target lifestyle and may shorten the path to financial independence. A higher-cost move may do the opposite.

The FIRE variants share this same math with different spending assumptions: Lean FIRE (a smaller budget), Chubby FIRE (roughly $100k–$150k a year, about $2.5M–$3.75M at a 4% rate), and Fat FIRE (roughly $200k+ a year, about $5M+). The dollar targets are simply annual spending divided by the withdrawal rate; the “Lean / Chubby / Fat” labels are community conventions rather than official thresholds.

The Retirement, Retirement Withdrawal, Roth Conversion, and HSA calculators work in today’s dollars: contributions and withdrawals grow with inflation and the portfolio compounds at an inflation-adjusted “real” return, so results reflect present-day buying power. Taxes on traditional retirement withdrawals and Roth conversions use the same federal and state engine as the rest of the site, treated as ordinary income (no FICA); Illinois, Pennsylvania, Mississippi, and the nine no-income-tax states are handled as exempting qualified retirement income. HSA figures use the 2026 IRS limits, with California and New Jersey modeled as not conforming to the federal HSA exemption.

Market volatility (Monte Carlo): the Retirement and Retirement Withdrawal calculators offer an optional “market ups & downs” view that runs 5,000 simulated market histories, drawing each year’s return from a lognormal distribution centered on your expected return at a chosen volatility (Conservative, Balanced, Aggressive, or custom). It reports a range of outcomes and, for withdrawals, a success rate that captures sequence-of-returns risk. The simulation uses a fixed random seed, so the same inputs always reproduce the same result. It is a model of risk, not a prediction, and does not use historical return sequences.

Not every number on the site is the same kind of input. In general, the models rely on three different layers:

• Rule-based inputs: examples include tax brackets, filing status logic, and structured formula-based calculations.
• Modeled estimates: examples include housing assumptions, monthly essentials, and affordability comparisons built from location data.
• Comparison heuristics: examples include weighted affordability logic, comfort signals, and scenario-planning shortcuts used to keep the tools practical.

That distinction matters because some outputs are closer to structured formula results, while others are best treated as directional planning estimates rather than exact figures.

Relocation by Numbers uses a combination of public tax parameters, housing and cost assumptions, internally maintained location data, and comparison logic built for planning usefulness across the site.

Depending on the calculator, inputs may come from structured tax assumptions, city or state cost defaults, rent and housing parameters, relocation cost estimates, and internal modeling designed to compare locations on a consistent basis.

Because taxes, housing markets, living costs, and international rules change over time, assumptions may be revised as models improve or newer data becomes available.