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Loan & Mortgage Calculator

Loan & Mortgage Calculator

Monthly payment, full amortization schedule and how extra payments shorten the loan

Loan

Extra payments

Extra amounts go straight to principal — the monthly payment stays the same but the loan ends sooner.

Examples

Typical mortgage

Input
250,000 · 6.5% · 20 years
Output
Payment ≈ 1,865/mo · Total interest ≈ 197,600 · Payoff 240 months

Early payments are mostly interest — the schedule shows the split line by line.

Extra 200/month

Input
Same loan + 200 extra
Output
≈ 2 years earlier · ≈ 23,000 interest saved

Extras shorten the term instead of changing the payment — the tool quantifies both.

About this tool

The monthly payment comes from the standard annuity formula; everything after that is a month-by-month simulation of the amortization schedule — interest on the remaining balance, principal from what's left, extras going straight to principal.

Because the schedule is simulated, extra payments show their real effect: fewer months, less interest, with both figures reported explicitly and the balance curve overlaid against the no-extras baseline.

How to use

  1. Enter loan terms

    Amount, annual rate, term in years — and optionally an extra monthly amount toward principal.

  2. Read the payment

    Monthly payment, total interest, total paid and payoff length update instantly.

  3. Test extra payments

    Add 100–300 extra per month and watch interest saved and months cut appear.

  4. Export

    Download the amortization schedule as CSV or copy the summary for comparison shopping.

Use cases

Mortgage shopping

Compare rate/term combinations on total cost, not just the headline payment.

Prepayment planning

Decide whether an extra monthly amount fits the budget by seeing exactly what it saves.

Common mistakes

Mistake:Assuming extras reduce next month's required payment

Fix:On fixed annuities extras shorten the term; the payment stays constant until payoff.

Mistake:Ignoring total interest

Fix:A lower payment over a longer term often costs more — always compare total paid.

Frequently asked questions

References & standards