Stop Guessing. Calculate Your Real Spread.

Most financial advice ignores tax-drag. Savings accounts and stock dividends lose up to 40% of their growth to federal and state brackets. This calculator reveals the mathematically correct path.

1

Tax Bracket Analysis

Enter your ordinary income and state preset. We parse your AGI to apply federal ordinary, capital gains, and NIIT rates.

2

True Cost of Debt

Input your debt rate. If it's a student loan or mortgage, we'll factor in itemization caps and interest deductions.

3

Verdict Centerpiece

View your guaranteed payoff spread compared side-by-side with 5 major tax-sheltered and taxable asset classes.

Interactive Calculator Panel
01 / Inputs SAFE
$
$10,000$500,000

OBBBA car loan deduction is only allowed on US-assembled vehicles.

%
$
02 / The Verdict ConsolePAYOFF_PREFERRED
Compare Against:
Spread-1.79%Annualized

Guaranteed Early payoff beats HYSA / CD by 1.79% Spread

Math strongly favors paying off your car_loan debt. Doing so guarantees an effective, tax-free return of 4.68%, beating the tax-adjusted investment yield of 2.89% by 1.79%.

DEBT_RATE: 4.68%
INVEST_RATE: 2.89%
Refinance & Pay DownCan't pay off immediately with cash? Refinance to a lower rate to reduce interest drag while you pay it down.
Check Lower Rates

*Estimates only. Not financial or tax advice. View full disclaimers below.*

03 / Comparative Yield Grid5.85% STATE_TAX
Asset ClassNominalFed DragState DragAfter-TaxSpread vs Debt
🎯 Payoff CAR LOAN6.00%--4.68%(Guaranteed)
HYSA / CD4.00%22.0%5.9%2.89%-1.79%
T-Bills (3-Mo)4.15%22.0%0.0%3.24%-1.44%
Taxable Stocks8.00%0.9%0.0%6.92%+2.24%
Roth / HSA8.00%0.0%0.0%8.00%+3.32%
Traditional IRA8.00%34.2%9.1%4.53%-0.15%

Stocks assume an index fund compounding over 10 years with a 1.3% qualified dividend drag, capital gains deferred until sale. T-Bills are state tax exempt. Debt payoffs yield a guaranteed return.