🇺🇸 US Income & Net Worth Percentile

Pick a state and county on the map (or search by name), enter your gender, marital status, pre-tax income, net worth, and 401k balance, and see where you rank against real US Census Bureau / Federal Reserve data — county, nationwide, and by age band. Every calculation runs 100% locally in the browser — no API calls, no backend.

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Data & calculation logic

• data/us/stateIncome.json / data/us/countyIncome.json / data/us/nationalIncome.json — median household income + percentile anchor tables per state/county/nation. Source: US Census Bureau ACS 5-Year (and, for states, latest 1-Year) estimates. Regenerate with npm run fetch:census (requires a Census API key, see scripts/fetchCensusData.ts).
• data/us/netWorthPercentilesUS.json — nationwide net worth percentile anchors. Source: Federal Reserve Survey of Consumer Finances.
• data/us/401kByAge.json — average/median 401k balance by age band. Source: Vanguard, How America Saves.
• data/us/incomeByAge.json / data/us/netWorthByAge.json — median income / average net worth by age band, used only to rescale a user's value against the nationwide percentile curve above ("top X% nationwide for your age") — see each file's meta.note for how the six age bands map onto the coarser brackets ACS/SCF actually publish.
• lib/percentileTable.ts — shared log-log interpolation percentile calculator.
• lib/usIncomeCalc.ts — looks up income/net worth/401k percentiles for a given state/county/age band from the data above.
• lib/usInput.ts — query-string codec for the input panel's answers, so they survive navigation from /us → /us/[state] → /us/[state]/[county].

Structure

middleware.ts                            # "/" -> /us or /kr by Accept-Language; /kr/* rewrites to /us/*
app/
  page.tsx                              # fallback redirect (middleware handles this first)
  us/
    page.tsx / UsHomeClient.tsx          # US map — pick a state
    [state]/page.tsx / UsStateClient.tsx  # county map + SEO content (median income, thresholds, county directory); picking a county starts the result flow
    [state]/[county]/page.tsx             # SEO landing page per county (ISR, revalidate=86400) — CTAs into /us/result.
                                           # Old single-page result links (?d=...) redirect there via middleware.ts instead.
    about/ · privacy/ · contact/          # static info pages
    result/
      page.tsx / DashboardResultClient.tsx  # unified result dashboard (?st=&co=&d= carry state), see below
      overall/ state/ demographic/          # redirect stubs -> /result, kept so old shared links don't 404
data/us/
  stateIncome.json / countyIncome.json / nationalIncome.json
  netWorthPercentilesUS.json / 401kByAge.json / stateMeta.ts
  incomeByAge.json / netWorthByAge.json
lib/
  usIncomeCalc.ts / usInput.ts / usFormat.ts / usGeo.ts / percentileTable.ts
  i18n.ts                                # ko/en copy
  serverLocale.ts / seo.ts / useLocaleBase.ts  # /us vs /kr locale plumbing
  legacyResultRedirect.ts                # shared redirect for the retired /result/overall|state|demographic routes
components/us/
  UsMap.tsx / UsGeoList.tsx / UsInputPanel.tsx / UsResultCard.tsx / UsShell.tsx / Footer.tsx
  result/                                 # shared pieces for the result dashboard

Result flow

Picking a county navigates to /us/result?st=<state>&co=<county>&d=<answers> — one scrolling dashboard with every percentile (national/state/county/age/net worth/401k) computed up front, plus the share card and "compare with a friend" link near the top. It's a real page (own URL, works with browser back) that re-derives everything from the query string on each render, same as before. /kr/result serves the same page in Korean via the middleware rewrite. The old three-step routes (/result/overall, /result/state, /result/demographic) still exist as redirect stubs so old shared links keep working, but they're disallowed in robots.txt and non-canonical — new links should point at /result directly.

Local dev

npm install
npm run dev

Open http://localhost:3000

Deploy (Vercel)

vercel

AdSense

• The root layout emits the AdSense account meta tag. After shared d/lang query parameters are removed, it loads Google's Auto ads script using the public publisher ID constant in components/ads/AdSenseScript.tsx. It does not load on compare-invite pages, whose path contains encoded calculator answers. The loader does not depend on Netlify environment variables or a production-host check.
• NEXT_PUBLIC_ADSENSE_CLIENT_ID and NEXT_PUBLIC_SITE_URL still gate manually placed <AdSlot /> units in lib/ads.ts; they are not required for the Auto ads loader.
• public/ads.txt — 완료됨: the real publisher ID (pub-7379794980536826) is in place, no longer a placeholder. Keep it in sync with the publisher ID constant and any configured NEXT_PUBLIC_ADSENSE_CLIENT_ID — AdSense won't serve ads on the domain without a matching ads.txt entry.