Sources

We aim to ground every tax parameter in an authoritative source. The 2025 federal figures come from the IRS and SSA, and state income tax rates for all 50 states and Washington, D.C. are compiled primarily from the Tax Foundation's annual survey and cross-checked against state revenue departments where available. The references below are the authorities we rely on; results remain estimates and should be verified for your specific situation.

• Internal Revenue Service (IRS)

  Federal income tax brackets, standard deductions, and Additional Medicare Tax thresholds.

• Social Security Administration (SSA)

  Social Security wage base limit and contribution rates.

• Tax Foundation — State Individual Income Tax Rates and Brackets

  Primary reference for 2025 state income tax rates, brackets, and standard deductions across all 50 states and D.C.

• California Franchise Tax Board (FTB)

  California state income tax brackets and standard deduction.

• Colorado Department of Revenue

  Colorado flat income tax rate.

• Georgia Department of Revenue

  Georgia 2025 flat rate update (HB 111) used to cross-check the state rate.

• Louisiana Department of Revenue

  Louisiana's 2025 move to a single flat income tax rate.

• Texas Comptroller

  Confirmation that Texas levies no state personal income tax.

If you spot an inaccuracy, the rate configs live in app/lib/tax/ and can be corrected per state without changing the calculation engine.