Cernarus

Boat Loan Payment Calculator with Bi-Weekly Payments

This calculator compares monthly and bi‑weekly repayment plans for a boat loan. It supports true bi‑weekly amortization (26 payments per year) and accelerated bi‑weekly payments by splitting the monthly payment in half.

Enter the loan amount, APR, term, and any recurring extra payment. Results show scheduled payment amounts, number of payments, total paid and total interest for each method so you can compare cost and payoff speed.

Updated Nov 10, 2025

Amortization with payments every two weeks (26 payments per year). Uses the bi‑weekly periodic rate to compute level payments over the total 26*years periods.

Inputs

Results

Updates as you type

Bi‑weekly payment

$30,468.75

Bi‑weekly payment (with extra)

$30,468.75

Payments (count)

130

Total paid over life of loan

$3,960,937.50

Total interest paid

$3,930,937.50

Effective annual rate (EAR)

2400.00%

OutputValueUnit
Bi‑weekly payment$30,468.75currency
Bi‑weekly payment (with extra)$30,468.75currency
Payments (count)130—
Total paid over life of loan$3,960,937.50currency
Total interest paid$3,930,937.50currency
Effective annual rate (EAR)2400.00%%
Primary result$30,468.75

Visualization

Methodology

Monthly method uses standard amortization with 12 periods per year and converts the nominal APR to a monthly periodic rate.

True bi‑weekly method converts the nominal APR to a bi‑weekly periodic rate (divide APR by 26) and amortizes over 26 × years periods.

Split bi‑weekly method takes the monthly amortized payment and pays half every two weeks (26 payments/year), often creating an accelerated payoff because 26 half‑monthly payments exceed 12 full monthly payments.

Worked examples

Example: $30,000 loan, 6% APR, 5 years. Monthly payment ≈ calculated using APR/12. True bi‑weekly payment uses APR/26 and 130 payments over 5 years.

If you split monthly payment in half and pay bi‑weekly, you typically make the equivalent of 13 monthly payments per year (26 half payments), which reduces principal faster and lowers total interest.

Key takeaways

Use the monthly method to see lender‑standard amortization. Use true bi‑weekly or split bi‑weekly to compare accelerated payoff options.

This calculator provides estimates; consult your lender for precise schedules, fees, and the exact application of payments.

Further resources

Expert Q&A

Is bi‑weekly always cheaper than monthly?

True bi‑weekly schedules and split‑monthly schedules can reduce interest compared to monthly payments because they increase the number of payments per year (26 vs 12). Savings depend on interest rate, term, and whether your lender applies payments immediately to principal.

What is the difference between APR and effective annual rate (EAR)?

APR is the nominal annual rate often used for disclosure. EAR accounts for compounding within the year and shows the annualized effect: EAR = (1 + periodic_rate)^(periods_per_year) - 1.

Do results match my lender's statements exactly?

This tool uses standard annuity formulas and assumes payments are applied immediately and without fees. Lenders may use different day‑count conventions, rounding rules, timing, or fees that change results. Use this calculator for estimates and comparison only.

How should I enter extra payments?

Enter recurring extra principal paid each scheduled period. One‑time lump sums are not modeled here and must be applied separately or with a full amortization schedule tool.

What rounding or precision is used?

Displayed results are rounded for presentation. Internal calculations assume exact arithmetic; small differences can occur due to rounding in lender schedules.

Sources & citations