Auto Loan Balloon Calculator
This calculator covers common auto-loan scenarios that include a balloon payment at the end of the term. Use it to compute the periodic payment given an upfront loan and final balloon, compute the balloon given a payment, infer the loan principal from payment + balloon, or estimate remaining balance after a number of payments.
The tool assumes a nominal annual percentage rate (APR) converted to a periodic rate by dividing by the number of payments per year (for example, 12 for monthly). The balloon is treated as a lump sum payable at the final scheduled period.
Compute the fixed periodic payment when a lump-sum balloon is due at the end of the term.
Inputs
Advanced inputs
Common inputs
Balloon details (used by several methods)
Payment input (used by payment-based methods)
Payment and balloon (loan calculation)
Balance after N payments
Results
Periodic payment (per period)
$303.90
| Output | Value | Unit |
|---|---|---|
| Periodic payment (per period) | $303.90 | — |
Visualization
Methodology
Calculations use standard time-value-of-money formulas. Present value of the payment stream plus the discounted balloon equals the loan principal. Solve the algebraic form appropriate to the requested unknown.
Periodic interest rate r is APR / 100 / payments_per_year. Number of periods n is term_years * payments_per_year. Annuity factor for a level payment is (1 - (1 + r)^-n) / r. Present-value and future-value relationships follow established finance conventions.
Worked examples
If you borrow 20,000 with a 5% APR, 5-year term, monthly payments and a 5,000 balloon, the calculator returns the monthly payment required to amortize to that balloon.
If you make a fixed monthly payment and want to know the final balloon required for a given principal and term, switch to the balloon calculation mode and enter the payment amount.
Key takeaways
Use the mode selector to pick whether you want payment, balloon, loan principal, or outstanding balance calculations.
Provide nominal APR, payment frequency, term, and the known monetary values. Verify results against lender disclosures and consider rounding and fees.
Further resources
Expert Q&A
Does this calculator use APR or nominal rate?
It expects a nominal APR value. It converts APR to a periodic rate by dividing by the number of payments per year. It does not compute finance charges under specific disclosure rules; use disclosed APR from your lender for regulatory comparisons.
What happens at zero interest rate?
The algebraic forms shown assume a positive interest rate. When the rate is zero, the periodic payment simplifies to (loan_amount - balloon_amount) divided by the number of periods. The tool provides guidance for zero-rate cases but numeric engines may require special handling to avoid division by zero.
Are results exact?
Results are based on standard closed-form formulas and floating-point arithmetic. Rounding, payment timing conventions, compounding differences, and lender-specific fees will affect real-world amounts. See accuracy caveats below.
Sources & citations
- NIST - Guidelines and best practices for financial calculations — https://www.nist.gov
- ISO - Financial services standards — https://www.iso.org
- IEEE - Recommended practices for numeric software — https://www.ieee.org
- OSHA - Not applicable for finance, included for compliance reference — https://www.osha.gov