🏡 Mortgage / Loan Calculator

Fixed-rate amortization with extras. Choose payment frequency, add interest-only months, include extra payments, and export the schedule — all offline.

Loan inputs

Loan amount

Principal (e.g. 250000)

Interest rate (APR %)

Annual nominal rate

Term — years

Term — months

Extra months in addition to years

Payment frequency

Interest-only months

Principal doesn’t reduce during this period (extras still reduce)

Start date

Used to generate due dates

Escrow add-on / period

Taxes & insurance — doesn’t affect payoff

Extra per period

One-time extra

Applied at period # below

One-time at period #

1 = first payment; 0 = never

Show rows

Recalculate fixed payment after I/O at then-current balance Round cents each row

With extra payments, total term shrinks. Final row auto-adjusts to clear remaining cents.

Your inputs are saved locally.

Results

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Base payment / period

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With escrow / period

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Total interest

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Time to payoff

Assumes nominal APR distributed evenly across the selected payment frequency (e.g., monthly APR/12). For biweekly/weekly, interest accrues per period at APR/26 or APR/52.

#	Date	Payment	Interest	Principal	Extra	Balance

Display is limited by “Show rows”. CSV export always includes the full schedule.