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Methodology

Every figure on this site traces to a named, public, government data source. We don’t license private indexes or use proprietary scores. This page lists exactly what we use, what time period each dataset covers, and how the core calculations work.

Take-home pay and state income tax

Federal income tax

We apply the 2025 IRS federal income tax brackets and standard deductions published by the Internal Revenue Service. We use the standard deduction for all calculations (not itemized deductions), which is the correct assumption for the majority of filers. Brackets and deduction amounts are sourced directly from IRS Revenue Procedure 2024-61 and related official publications.

State income tax

State income tax rates, brackets, and standard deductions are sourced from the Tax Foundation’s 2025 state income tax data. We model the states we cover using each state’s published rate schedule and apply the state’s own standard deduction or personal exemption where applicable.

Nine states currently levy no general income tax on wages: Alaska, Florida, Nevada, New Hampshire, South Dakota, Tennessee, Texas, Washington, and Wyoming. For wage and salary income Washington’s effective rate is zero; WA does impose a separate capital gains excise tax (currently 7% on investment gains above ~$262,000–$278,000/yr; a new 9.9% rate on gains above $1M takes effect January 1, 2028), which this calculator doesn’t model — consistent with not modeling capital gains income for any state. Local and city income taxes are not modeled.

FICA (Social Security and Medicare)

FICA withholding is calculated using Social Security Administration rates and wage base limits for 2025:

  • Social Security: 6.2%, applied to the first $176,100 of wages
  • Medicare: 1.45% on all wages
  • Additional Medicare surtax: 0.9% on wages above $200,000 (single filers) or $250,000 (married filing jointly)

Cost-of-living adjustment

Cost-of-living comparisons use the Bureau of Economic Analysis (BEA) Regional Price Parities (RPPs), the most recent available annual release (2024 data). RPPs measure the differences in price levels across states and metropolitan areas for a given year. A value of 105 means prices in that state are 5% above the national average; a value of 92 means they are 8% below.

We break out four RPP components separately: housing, goods, utilities, and services (labeled “other services” in the BEA dataset). Each is shown as a percentage above or below the national average of 100.

The “equivalent lifestyle” figure is the salary you would need in the destination state to maintain the same real purchasing power as your current take-home pay. It is calculated by scaling your take-home pay by the ratio of the two states’ overall RPP values.

We chose BEA RPPs over private cost-of-living indexes (such as the C2ER index licensed by many financial websites) because the methodology is fully public, maintained by a federal agency, and available at no cost.

Migration data

State-to-state flow counts

Migration flow counts (how many people moved from each state to each other state) come from the U.S. Census Bureau’s American Community Survey (ACS) 1-Year Estimates, 2024 vintage. The 2024 ACS 1-year estimates are the most recent published state-to-state migration flow data.

Average mover income

The average income figure shown for each migration corridor (e.g., “average income, CA→TX movers”) comes from the IRS Statistics of Income (SOI) State-to-State Migration Data, 2022–2023 filing year. This figure represents the average adjusted gross income per tax return for filers who moved between those two states. Because joint filers count as a single return, this is closer to a household income figure than a per-person figure.

Climate data

Temperature and precipitation figures (average annual high, average annual low, average precipitation, days above 90°F, days below 32°F) come from NOAA U.S. Climate Normals, the 1991–2020 30-year average. Climate normals are the standard reference period used by climatologists; they are updated every decade.

State-level values are derived by aggregating station-level normal data across each state. Not all stations cover all variables, so some values may reflect a subset of available stations within a state.

Natural hazard risk

Hazard risk data comes from FEMA’s National Risk Index (NRI). The NRI produces composite risk scores for 18 natural hazard types at the county level, incorporating expected annual loss, social vulnerability, and community resilience.

We aggregate county-level NRI scores to the state level. Because the NRI scores reflect total expected loss (not per-capita or per-resident risk), densely populated states tend to score higher. State-level ratings (Very Low through Very High) are approximated from FEMA’s county-level score thresholds; FEMA publishes official ratings at the county level only.

Hazard types modeled individually: flooding, coastal flooding, wildfire, hurricane, tornado, and earthquake.

What we don’t model (yet)

  • Local and city income taxes — not yet included. A few cities (New York City, Philadelphia, Detroit) levy meaningful local income taxes that would reduce take-home pay further.
  • Washington capital gains excise tax — WA’s capital gains excise tax (7% on investment gains above ~$262,000; 9.9% above $1M effective January 1, 2028) is not modeled, consistent with how capital gains are excluded for all states in this calculator.
  • Itemized deductions — we apply the standard deduction for all filers.
  • Granular cost-of-living subcategories — the BEA RPPs break out housing, goods, utilities, and services, but not finer categories like groceries, gas, or health insurance individually.
  • School quality data — in progress, planned to use NAEP and NCES federal education data.

Questions about a specific calculation? Email info@chasinggreenergrass.com.