Every finance manager knows how to hide extra profit — called "leg" in the back office — inside your monthly payment instead of listing it as a separate charge. This tool shows you the payment your credit actually earned, then checks it against what they're closing you at. If the two don't match at the same rate, the gap is financed debt you didn't agree to.
Every retail installment contract is legally required to disclose these — look for the Truth-in-Lending box.
The "Amount Financed" box on your contract — not the car's price, the actual loan amount.
Typical APR by credit tier (new car, 2026 averages): 720+ ≈ 6–8% · 660–719 ≈ 9–11% · 600–659 ≈ 13–16% · under 600 ≈ 18%+. Used cars usually run 2–4 points higher.
Type in the payment on the contract in front of you — same rate, same term. If it's higher than your real number above, the extra isn't a rate problem. It's a bigger loan than the deal calls for.
"Packing" means rolling extra products — GAP insurance, an extended warranty, paint and fabric protection, VIN etching, a service contract — into the amount financed instead of listing them as line items you'd have to approve one by one. Roll enough of it in and a $700 payment can look completely normal, even though the car itself only justified $600.
It's legal because you technically sign for every page. It works because almost nobody reverse-engineers their own payment to check whether it matches the price of the car they agreed to buy. That's exactly what this tool does for you, before you sign anything.
I'll send your numbers plus the exact questions to ask the finance manager to get any packed extras removed or itemized. Free, no spam.
Packed payments, financed fees, yield-spread markups — the finance-office playbook isn't just for cars. See your real mortgage payment, MI included.
Open the Mortgage Calculator →Estimates for education only — not financial, legal, or credit advice. This tool checks whether your payment matches your contract's own disclosed numbers; it can't detect every dealer tactic, and your actual contract is the final word. Confirm anything that looks off with your lender before signing.