Methodology, Sources & Editorial Policy

This page explains where the numbers on LifeCalc come from, how the 32 calculators use them, and what they leave out. Datasets were last verified on September 1, 2026. LifeCalc is published by Honey Badger Labs LLC; the author is Frank Sterling (a disclosed pen name).

Data sources

Federal income tax brackets and standard deductions (2026)

Taken from IRS Revenue Procedure 2025-32, which sets the 2026 inflation adjustments, including the changes made by the One Big Beautiful Bill Act. We checked the standard deductions used here ($16,100 single, $32,200 married filing jointly, $24,150 head of household) and the 10% bracket edge against the published text. Source: IRS Rev. Proc. 2025-32.

Payroll taxes (FICA)

Social Security 6.2% up to a wage base of $184,500, Medicare 1.45%, and the 0.9% Additional Medicare Tax above $200,000. The wage base is the Social Security Administration’s 2026 figure; see the SSA’s contribution and benefit base page.

State income tax brackets (51 jurisdictions)

Bracket tables for the 50 states and DC, stored in state_tax_brackets.json. They are checked against each state tax agency’s published rate schedules during the monthly update. States with no wage income tax carry an empty table. Local (city and county) income taxes are not included.

Retirement contribution limits

2026 limits used: 401(k) elective deferral $24,500 and IRA $7,500, from the IRS annual retirement plan limit announcement (IRS 401(k) limits).

Cost-of-living indices (51 states/DC, 100 metros)

These are LifeCalc’s own compiled index values, where 100 is the national baseline. They are estimates informed by BLS Consumer Price Index releases and regional price parity data during the monthly update, not an official government statistic; the government does not publish a single city-to-city cost-of-living index. Treat them as directional. Metro population comes from Census Bureau estimates.

Salary data (30 occupations, 20 metro multipliers)

Median salaries per occupation follow the Bureau of Labor Statistics Occupational Employment and Wage Statistics. The entry and senior levels and the metro multipliers are LifeCalc estimates around that median, not BLS figures.

Paid family leave programs (13 state and DC programs)

Weeks, wage replacement, weekly maximums and waiting periods from each state agency’s program pages; the agency link is listed on each state’s family leave page. Program details change often, so always confirm with the agency before relying on a figure.

Childcare and baby cost data

Childcare costs by state and metro follow published cost-of-care surveys and Department of Labor childcare price data; baby costs use ranges (low, mid, high) informed by USDA Expenditures on Children by Families. These are averages, and local prices vary widely.

How the calculators work

Tax and paycheck calculators

Federal tax is progressive: your gross income minus the standard deduction is run through each bracket. FICA is added, then state tax from the state bracket table. Limits: state tax is applied to gross income with no state-specific deductions or credits; itemized deductions, credits (such as the child tax credit), AMT, and local taxes are not modeled. Results are estimates of a typical W-2 situation, not a tax return.

Scenario comparison, relocation, and cost-of-living calculators

Each scenario computes take-home pay, then subtracts housing and other spending scaled by the location's cost-of-living index (non-housing spending defaults to 35% of income). Ten-year projections use editable defaults: 3% salary growth, 7% investment return, 2.5% inflation. Limits: the index is a city-level average, and your own rent and spending will differ. Projections are illustrations, not forecasts.

Rent vs buy, mortgage, affordability and refinance calculators

Standard amortization math. Rent vs buy defaults: 6.5% mortgage rate, 20% down, 1.2% property tax, 0.5% insurance, 1% maintenance, 3.5% annual appreciation, and the opportunity cost of the down payment. All are editable. Limits: real rates, taxes and insurance vary by lender and location, and mortgage interest deduction effects are simplified.

Retirement, savings, compound interest and CD calculators

Closed-form compound growth with regular contributions, employer match, and IRS limits. The retirement calculator uses the 4% withdrawal guideline as a rule of thumb. Limits: constant return assumptions ignore market volatility and sequence-of-returns risk.

Debt, student loan, auto and personal loan calculators

Month-by-month amortization with optional extra payments; snowball vs avalanche ordering for multiple debts. Limits: fixed rates only; fees, deferment, forgiveness programs and variable rates are not modeled unless a field is provided.

Self-employment, capital gains and salary calculators

Self-employment tax uses the 15.3% combined rate on 92.35% of net earnings up to the wage base. Capital gains uses short-term (ordinary) and long-term (0/15/20%) rates plus the 3.8% Net Investment Income Tax. Limits: no loss carryovers, wash-sale rules, or state-specific treatment beyond the state bracket table.

Family leave, baby cost and divorce calculators

Family leave applies each state program’s replacement rate and weekly cap to your wage. Baby cost sums line items from low/mid/high ranges. The divorce calculator provides rough cost and division illustrations. Limits: eligibility rules, employer top-ups and state law details are simplified; these tools do not replace the agency or an attorney.

All calculations run in your browser. The numbers you enter are only sent to our servers if you choose to email yourself the results (see the privacy policy).

Update cadence

A scheduled monthly job re-checks the datasets above against the sources listed and updates any that changed. Tax brackets get extra attention at year boundaries (November to January), when the IRS and states publish new figures. The “data last verified” date shown in the site footer (September 1, 2026) is updated only when a verification pass has actually been completed; it is not the current date. Guides carry their own publication dates and may lag the data; where a guide and a calculator disagree, trust the calculator and tell us.

Editorial policy

  • Guides are written and edited under the pen name Frank Sterling. See the author page for what that means and what it does not (no professional licenses are claimed).
  • Going forward, guides may be drafted with AI assistance, and are edited and fact-checked against the sources above before publication.
  • Figures should come from the calculators’ datasets or a cited official source. Where a number is an estimate or a default assumption, the guide should say so.
  • Guides that are thin, redundant or tied to short-lived news are consolidated or removed from search indexing instead of being left to go stale.
  • LifeCalc is free to use. It does not sell financial products or take payment for placement in calculators or guides.
  • Nothing here is financial, tax, or legal advice.

Corrections

If you find an error, email hello@lifecalc.co with the page URL, what looks wrong, and a source if you have one. We check reports against the primary source, fix confirmed errors, and note material corrections in the changelog below.

Changelog

  • 2026-09-29: Consolidated overlapping guides, added sources and methodology, added author and publisher pages.
  • 2026-09-01: Monthly data verification pass.