{{ frequencyLabel }} Housing Payment
{{ currencySymbol }} {{ format(totalHousingPayment) }}
{{ summaryLine }}
{{ currencySymbol }} {{ format(amountFinanced) }} financed {{ formatPercent(loanToValue, 1) }}% LTV {{ currencySymbol }} {{ format(cashToClose) }} cash to close {{ frequencyLabel }} PI {{ currencySymbol }} {{ format(periodicPiPayment) }} {{ frequencyLabel }} escrow {{ currencySymbol }} {{ format(periodicEscrow) }} PMI {{ currencySymbol }} {{ format(firstPeriodPmi) }} Save {{ currencySymbol }} {{ format(comparison.interestSaved) }}
{{ currencySymbol }}
{{ currencySymbol }} %
% / yr
yrs mos
{{ currencySymbol }}
{{ currencySymbol }} at pmt
{{ currencySymbol }}
% / yr {{ currencySymbol }} / yr
{{ currencySymbol }} / yr
{{ currencySymbol }} / mo
% / yr
Metric Value Copy
{{ row.label }} {{ row.display }}
{{ note.title }}

{{ note.body }}

Current plan
{{ currencySymbol }} {{ format(totalHousingPayment) }} / {{ frequencyLabel.toLowerCase() }}
Payoff in {{ payoffReadable }}
Total interest: {{ currencySymbol }} {{ format(totalInterest) }}
Finish: {{ payoffDateLabel }}
No acceleration
{{ currencySymbol }} {{ format(comparison.baseTotalHousingPayment) }} / {{ frequencyLabel.toLowerCase() }}
Payoff in {{ comparison.basePayoffReadable }}
Total interest: {{ currencySymbol }} {{ format(comparison.baseTotalInterest) }}
Finish: {{ comparison.basePayoffDateLabel }}
Save {{ currencySymbol }} {{ format(comparison.interestSaved) }} interest Finish {{ comparison.periodsSaved }} payments earlier Cut PMI by {{ currencySymbol }} {{ format(comparison.pmiSaved) }} {{ currencySymbol }} {{ format(extraPaymentValue) }} extra each payment {{ currencySymbol }} {{ format(lumpSumValue) }} lump sum
Metric No acceleration Current plan Change Copy
{{ row.label }} {{ row.baseDisplay }} {{ row.currentDisplay }} {{ row.deltaDisplay }}
Current milestones
Milestone When Balance
{{ row.label }} {{ row.when }} {{ row.balanceDisplay }}
No-acceleration milestones
Milestone When Balance
{{ row.label }} {{ row.when }} {{ row.balanceDisplay }}
Add recurring extra principal or a one-time lump-sum payment in Advanced to compare an accelerated payoff path against the standard mortgage schedule.
Pmt Date Total Principal Interest Escrow PMI Balance Equity Copy
{{ row.idx }} {{ row.dateLabel }} {{ row.totalPaymentDisplay }} {{ row.principalDisplay }} {{ row.interestDisplay }} {{ row.escrowDisplay }} {{ row.pmiDisplay }} {{ row.balanceDisplay }} {{ row.equityDisplay }}
Year Payments Principal Interest Escrow PMI Ending balance Ending equity Copy
{{ row.year }} {{ row.totalPaymentDisplay }} {{ row.principalDisplay }} {{ row.interestDisplay }} {{ row.escrowDisplay }} {{ row.pmiDisplay }} {{ row.balanceDisplay }} {{ row.equityDisplay }}

            
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Introduction:

A mortgage payment is a repeating split between interest on the remaining balance and principal that pays the loan down. That split matters because it shapes both affordability today and how quickly equity builds over time. This calculator turns that fixed-rate repayment problem into a period-by-period estimate you can inspect before you commit to a budget.

The package starts from the financed amount after down payment, applies the stated annual rate across either monthly or bi-weekly periods, and then builds an amortization schedule from the opening balance to payoff. It also lets you test recurring extra payments, a one-time lump sum, and an alternative compounding mode so you can compare how the same loan behaves under different assumptions.

That makes it useful for more than a single payment quote. You can compare a shorter term against a larger down payment, see how much of the first payment goes to interest, or decide whether an extra principal payment meaningfully shortens the loan. If you also need a household cash-flow view, the summary can add property tax, insurance, homeowners association dues, and private mortgage insurance.

One practical boundary matters early. The large summary figure is a budgeting number for one period, while the Amortization Schedule tracks the loan itself through Payment, Interest, Principal, and Balance. Recurring housing costs raise out-of-pocket cost, but they do not change the balance in this package.

Use the result as an educational estimate, not as financial advice or a lender quote. Real disclosures can differ because annual percentage rate (APR), escrow requirements, lender fees, changing taxes, and PMI cancellation rules are broader than the fixed assumptions modeled here.

Everyday Use & Decision Guide:

For a first pass, enter the home price, down payment, nominal interest rate, and term exactly the way they appear in the scenario you are comparing. Leave prepayments and add-on costs at zero until the base loan looks plausible. That gives you a clean benchmark before you start testing payoff strategies.

  • Use the summary badge for cash-flow screening. Use the first row of the Amortization Schedule when you want to know where the money goes between interest and principal.
  • Add Property tax, Insurance, HOA fee, and PMI rate only after the core loan is settled. They raise the summary payment, but the schedule and charts still describe loan repayment rather than escrow-style housing costs.
  • Change one prepayment lever at a time. A recurring Extra payment and a one-time Lump sum can both shorten payoff, but testing them separately makes the interest savings easier to understand.
  • If PMI does not appear, check the package rule instead of assuming a bug. The PMI rate control is shown only when Down payment is entered as a percentage, the percentage is < 20, and the PMI rate itself is > 0.

A lower computed payment does not automatically mean a cheaper mortgage in disclosure terms. Before you trust a comparison, match the package inputs against the lender's stated rate, APR, escrow lines, and repayment method.

Technical Details:

The package models a fixed-rate mortgage from the financed balance forward. First it derives loan amount from home price minus down payment. Then it chooses a period count from the term and payment frequency, computes a base principal-and-interest payment, and applies that payment against the balance until the loan reaches zero.

The first row often surprises readers because it is intentionally interest-heavy. Interest is charged on the full opening balance, so the early Principal share is smaller than it will be later in the loan. As the balance falls, each new period produces less interest and more principal, even when the scheduled payment stays level.

The interest-method selector deserves careful reading. In the current implementation, Monthly compounding (standard) and Simple interest (daily accrual) both reduce to the same period rate because the daily calculation is averaged back across the selected payment periods. Continuous compounding is the only option that materially changes the period-rate formula here, so it is the only mode that changes the base payment for the same stated annual rate.

Formula Core:

The base principal-and-interest payment follows the standard level-payment mortgage equation. If the rate is zero, the package falls back to a simple balance-divided-by-periods calculation.

P = L r 1 - ( 1 + r ) - n
Mortgage formula variables
Symbol Meaning Source
L Loan amount after the chosen down payment Derived from Loan amount and Down payment
r Per-period rate based on Interest rate, frequency, and interest method Computed
n Total payment periods across the full term Years × 12 or 26
P Base principal-and-interest payment before optional prepayments Computed

Schedule generation then becomes an iterative balance update. For each row, Interest equals prior Balance multiplied by the period rate. Principal is the base payment minus that interest, with any recurring Extra payment and any matching-period Lump sum added directly to principal. The package caps prepayment at the remaining balance so the final row does not overshoot payoff.

Budgeting Add-Ons:

The summary payment can include recurring housing costs, but those amounts are not added into the amortization balance. Property tax can be entered either as an annual percentage of home price or as a fixed annual amount. Insurance is treated as an annual premium, HOA dues as a monthly amount, and PMI as an annual percentage of the loan amount when the package's display rule is met.

Recurring cost treatment
Input How the package treats it Changes balance?
Property tax Annual percent of price or annual fixed amount, scaled into the selected payment period No
Insurance Annual premium scaled into the selected payment period No
HOA fee Monthly dues scaled into the selected payment period No
PMI rate Annual percentage of the loan amount, shown only when down payment is entered as a percent and remains below 20 No

Outputs, Comparability, and Limits:

Primary outputs
Output What it tells you
Monthly Payment or Bi-weekly Payment Budgeting figure for one period, including optional recurring costs and recurring extra payment
Amortization Schedule Row-by-row loan cash flow through Payment, Interest, Principal, and Balance
Payment Breakdown & Balance Stacked principal and interest bars with the remaining balance plotted against the same periods
Total Paid Share Total principal versus total interest across the built schedule
Cumulative Totals Running principal paid and running interest paid through the term

Comparisons are only fair when the loan amount, term, and rate convention are aligned across runs. APR is not the same thing as the nominal interest rate used in this formula, and the package does not model changing tax assessments, variable-rate resets, escrow cushions, or automatic PMI cancellation. Property-tax percentages stay tied to the entered home price, and PMI remains a flat annual percentage unless you remove it yourself.

All calculations happen in the browser with no server-side processing. Identical inputs produce identical schedules, which makes scenario comparison reliable so long as you remember that the model is fixed-rate and assumption-driven.

Step-by-Step Guide:

Use the controls in the same order a lender conversation normally unfolds: amount first, payment structure second, then optional prepayments and carrying costs.

  1. Enter Loan amount, Down payment, and the down-payment type. If the financed amount falls to 0 or below, the Amortization Schedule and charts disappear until the loan amount becomes positive again.
  2. Set Interest rate and Loan tenure. Check the summary badge and the first Payment row to confirm the scenario still looks realistic.
  3. Open Advanced and choose Payment frequency and Interest method. For a standard fixed-loan comparison, start with Monthly compounding (standard) unless you have a specific reason to test the other modes.
  4. Use Extra payment for a recurring principal add-on and Lump sum with at period for a one-time payoff event. Then compare the last Balance row and the Cumulative Totals chart against your baseline run.
  5. Add Property tax, Insurance, HOA fee, and PMI rate when you need a fuller carrying-cost estimate. If PMI rate is missing, switch the down payment to percent and keep it below 20.
  6. Read Amortization Schedule for row-level cash flow, then use Payment Breakdown & Balance, Total Paid Share, and Cumulative Totals to compare structure and payoff pace across scenarios.

When the summary figure, first-row split, and final payoff row all tell the same story you expect from your lender documents, the scenario is ready for planning use.

Interpreting Results:

Read the summary badge and the schedule as complementary views rather than duplicates. The badge is your per-period budgeting estimate. The schedule and charts describe how the loan balance changes.

  • If Principal starts small and grows later, that is normal fixed-rate amortization. Early periods are interest-heavy because the opening Balance is still large.
  • If down payment as a percentage is < 20 and PMI rate is > 0, the summary may rise from PMI while the payoff charts still show only principal and interest. If down payment is entered as a dollar amount, this package does not add PMI automatically.
  • A shorter schedule or smaller interest share usually means prepayment is working, but a lower number here does not prove the mortgage is cheaper overall. Verify the lender's APR, escrow lines, and PMI terms before you rely on the estimate.

Worked Examples:

Baseline thirty-year loan:

Enter a home price of $350,000, a 10% down payment, a 4.00% rate, a 30-year term, and monthly payments. The summary shows Monthly Payment of about $1,503.86. In the first Amortization Schedule row, Interest is $1,050.00, Principal is $453.86, and Balance falls to $314,546.14. That is a typical early-loan pattern: most of the payment is still serving interest, not yet crushing principal.

Recurring prepayment plus a one-time boost:

Keep the same loan, then set Extra payment to $200 and a Lump sum of $5,000 at period 24. The first Payment row rises to $1,703.86, and the schedule shortens from 360 rows to 281. Total interest drops from roughly $226,388 in the baseline run to about $168,472 in this prepayment run. The useful reading is not just the larger first payment, but the much earlier payoff horizon.

Troubleshooting a missing schedule:

Set a $350,000 price with a down payment above the price, such as 105% or a dollar down payment of $400,000. The package computes a non-positive loan amount, so no Amortization Schedule is built and the charts do not render. When that happens, fix the financed amount first. The package only builds results when loan amount > 0, payment > 0, and the term produces at least one period.

FAQ:

Why do standard and simple daily sometimes give the same payment?

Because of the package's current math. Simple interest (daily accrual) uses 365.25 days and then scales that back to the selected payment periods, which lands on the same per-period rate as the standard method for the monthly and bi-weekly options offered here.

Why is the summary payment larger than the Payment column in the schedule?

The summary can include recurring housing costs such as property tax, insurance, HOA dues, PMI, and any recurring extra payment. The schedule columns stay focused on the loan cash flow itself through Payment, Interest, Principal, and Balance.

Why did PMI not appear?

The package only shows PMI rate when Down payment is entered as a percentage and that percentage is < 20. Entering an equivalent dollar amount does not trigger the PMI field.

Does the package store my mortgage numbers?

No. The calculator runs in the browser, and copy, download, and document exports are generated locally from the values on the page.

What happens at a 0% rate?

The package skips the standard mortgage formula and divides the loan amount evenly across the total number of periods. That gives a flat principal payment with no interest component.

Glossary:

Amortization
The balance reduction path produced by repeated loan payments.
APR
A broader borrowing-cost disclosure than the nominal rate entered here.
PMI
Private mortgage insurance, a lender-protection cost on higher-LTV loans.
Period
One monthly or bi-weekly payment slot in the schedule.

References: