Fidamen

RV Loan Extra Payments Calculator with Extra Payments

This calculator shows how one-time or recurring additional principal payments change the amortization of an RV loan. It compares the baseline schedule (no extra payments) to scenarios with a single extra payment applied at a chosen payment number or a fixed extra added to every payment.

Use the fields to enter the loan amount, APR, term, and the extra payment choices. Results show new payoff time, estimated interest saved, and total amount paid under each scenario. This tool is for planning and estimates; exact figures depend on your lender's posting rules and day-count conventions.

Updated Nov 4, 2025QA PASS — golden 25 / edge 120Run golden-edge-2026-01-23

Governance

Record 19f6e8c8705f • Reviewed by Fidamen Standards Committee

Add a fixed extra amount to each payment (starting immediately) and compute new payoff time and interest savings.

Inputs

Advanced inputs

One-time extra settings

Recurring extra settings

Results

Updates as you type

Payment including recurring extra

$485.55

Payments required with recurring extra

—

Total paid (with recurring extra)

—

Interest saved

—

OutputValueUnit
Payment including recurring extra$485.55USD
Payments required with recurring extra—payments
Total paid (with recurring extra)—USD
Interest saved—USD
Primary result$485.55

Visualization

Methodology

Calculations use standard fixed-rate amortization formulas. Periodic interest rate r = APR / payments_per_year. Regular payment is computed by the closed-form annuity formula: payment = P * r / (1 - (1+r)^-N).

One-time extra: the outstanding balance just before the extra at payment k is computed from the closed-form balance formula. The extra reduces principal immediately; remaining payments are recomputed assuming the borrower continues the regular payment amount until payoff.

Recurring extra: a fixed additional principal amount is added to each payment. The new effective payment is regular_payment + extra; the remaining number of payments is calculated using the annuity payoff formula solved for n.

F.A.Q.

Will results match my lender's payoff exactly?

This calculator uses standard amortization math. Actual lender payoff amounts may differ due to daily interest accrual methods, rounding rules, fees, payment posting order, and whether the lender applies extra payments to principal immediately. Use results as an estimate and request an official payoff quote from your lender for exact amounts.

Can I enter extra payments that start later or end early?

This tool offers a one-time extra and a simple recurring-per-payment extra. For complex schedules (varying amounts or start/end ranges), please run multiple scenarios or consult an amortization schedule exported to a spreadsheet for custom schedules.

What input ranges and limits should I watch for?

Keep APR non-negative and realistic (typically 0–30%). Payments per year should be at least 1. Very small or zero periodic rates, zero extra amounts, or extra amounts that fully pay the loan immediately may produce edge results; the calculator includes no lender-specific fees or prepayment penalties.

Sources & citations

Further resources

Versioning & Change Control

Audit record (versions, QA runs, reviewer sign-off, and evidence).

Record ID: 19f6e8c8705f

What changed (latest)

v1.0.0 • 2025-11-04 • MINOR

Initial publication and governance baseline.

Why: Published with reviewed formulas, unit definitions, and UX controls.

Public QA status

PASS — golden 25 + edge 120

Last run: 2026-01-23 • Run: golden-edge-2026-01-23

Engine

v1.0.0

Data

Baseline (no external datasets)

Content

v1.0.0

UI

v1.0.0

Governance

Last updated: Nov 4, 2025

Reviewed by: Fidamen Standards Committee (Review board)

Credentials: Internal QA

Risk level: low

Reviewer profile (entity)

Fidamen Standards Committee

Review board

Internal QA

Entity ID: https://fidamen.com/reviewers/fidamen-standards-committee#person

Semantic versioning

  • MAJOR: Calculation outputs can change for the same inputs (formula, rounding policy, assumptions).
  • MINOR: New features or fields that do not change existing outputs for the same inputs.
  • PATCH: Bug fixes, copy edits, or accessibility changes that do not change intended outputs except for previously incorrect cases.

Review protocol

  • Verify formulas and unit definitions against primary standards or datasets.
  • Run golden-case regression suite and edge-case suite.
  • Record reviewer sign-off with credentials and scope.
  • Document assumptions, limitations, and jurisdiction applicability.

Assumptions & limitations

  • Uses exact unit definitions from the Fidamen conversion library.
  • Internal calculations use double precision; display rounding follows the unit's configured decimal places.
  • Not a substitute for calibrated instruments in regulated contexts.
  • Jurisdiction-specific rules may require official guidance.

Change log

v1.0.0 • 2025-11-04 • MINOR

Initial publication and governance baseline.

Why: Published with reviewed formulas, unit definitions, and UX controls.

Areas: engine, content, ui • Reviewer: Fidamen Standards Committee • Entry ID: 303e4faa5230