Fidamen

Personal Loan Payment Balloon Estimator

This estimator helps you determine either the balloon (remaining) principal due at a future date or the periodic payment required when a balloon is planned. It supports common payment frequencies and allows a separate amortization schedule for sizing scheduled payments.

Use the appropriate mode: provide your periodic payment to get the estimated balloon; or provide a target balloon to calculate the periodic payment needed. Results are estimates intended for planning and comparison, not a binding loan disclosure.

Updated Nov 30, 2025QA PASS — golden 25 / edge 120Run golden-edge-2026-01-23

Governance

Record e5e38fb8ea8c • Reviewed by Fidamen Standards Committee

Given a fixed periodic payment, compute the outstanding principal (balloon) after a specified number of years.

Inputs

Results

Updates as you type

Estimated balloon payment due

$14,176.25

OutputValueUnit
Estimated balloon payment due$14,176.25—
Primary result$14,176.25

Visualization

Methodology

Calculations use standard fixed-rate amortization mathematics. Periodic rate = annual rate divided by the number of payments per year. Balances are computed by compounding the principal and subtracting the accumulated principal repaid by regular payments.

Where the periodic rate is zero (0%), formulas reduce to simple principal less total payments. This tool follows widely accepted numerical practices and assumes payments are level and made at regular intervals.

Numerical operations and floating-point arithmetic adhere conceptually to the IEEE 754 floating-point standard for binary floating-point arithmetic. For secure handling of inputs and operational testing, development and deployment follow guidance from NIST and quality-management principles described by ISO standards.

Worked examples

Example 1: $10,000 loan, 6% annual rate, monthly payments, balloon after 5 years, payment $200 → estimator returns the remaining balance at 5 years.

Example 2: $20,000 loan, 5% annual rate, biweekly payments, target balloon $5,000 after 4 years → estimator returns the periodic payment required to reach that balloon.

F.A.Q.

How accurate are the results?

Results are precise to typical floating-point accuracy but are estimates only. They do not replace lender loan disclosures. Small rounding differences may occur due to frequency conversions and floating-point rounding (IEEE 754). For contract-level accuracy, consult your loan agreement or lender.

What if the interest rate is 0%?

If the annual interest rate is zero, the calculations reduce to principal minus total payments made: remaining balance = loan_amount - payment * number_of_payments. The general formulas that divide by the periodic rate are not used in that special case; please verify results manually if you enter a zero rate.

Does this include fees, taxes, or insurance?

No. This estimator only models principal and interest under level-payment assumptions. It does not include one-time fees, recurring fees, taxes, insurance, or payment timing differences (late fees, prepayment penalties).

Can I use different amortization and balloon schedules?

Yes. The tool allows a separate amortization period to size the scheduled payment, then computes the remaining balance at an earlier balloon date.

Is this legally binding?

No. This is an informational planning tool and not a loan agreement or regulatory disclosure. For legally binding terms, refer to your lender's official documents.

Sources & citations

Further resources

Versioning & Change Control

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

Record ID: e5e38fb8ea8c

What changed (latest)

v1.0.0 • 2025-11-30 • 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 30, 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 • 2025-11-30 • 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: 3e425da25b47