The second look before you sign.
Somewhere between the advertised price and the paper they slide across the desk, the number grows. SideEyeMath is a set of free calculators that itemize exactly how — built by someone who used to sit on the other side of that desk.
Auto · all 50 states
Out-the-Door Price
The sticker isn’t the price. Tax, title, doc fee, and the payment — itemized like the buyer’s order the finance office prints.
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Auto · Mortgage · Personal
Loan Payoff
Your real payoff date, what the loan truly costs, and exactly what an extra payment every month buys back.
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Auto · trade-ins
Negative Equity Rollover
Upside down on the trade? See how much of every new payment goes to a car you no longer own.
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Mortgage · lump sums
Recast vs. Refinance
Two ways to use a windfall, one clear verdict. We raise an eyebrow at the expensive one.
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