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Amortization Calculator

See your monthly payment and how the split between interest and principal changes over the life of a loan.

Original principal.
Annual rate.
Length of the loan.
Monthly payment
Total interest over the loan
Total of all payments
Interest in your first payment

Estimate for a fixed-rate, fully-amortizing loan. Escrow (taxes/insurance) and fees are not included. General information only.

No sign-up No ads Runs in your browser — your numbers never leave your device

What amortization means

Amortization is the schedule that pays a loan to zero with equal payments. Because interest is charged on the remaining balance, the interest portion is largest at the start and shrinks every month, while the principal portion grows — so your equity builds slowly at first and faster later.

Each month: interest = balance × monthly rate · principal = payment − interest

Quick FAQ

Why is early interest so high?

Interest is charged on the outstanding balance, which is largest at the beginning. That's why the first years of a 30-year mortgage build very little equity.

How do extra principal payments help?

They cut the balance that future interest is charged on, so every extra dollar early saves multiple dollars of interest and shortens the loan.

Related: loan calculator · mortgage payment calculator · refinance calculator · all free calculators.

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More questions

Is the Amortization Calculator free to use?

Yes. The Amortization Calculator is completely free, runs in your browser, and never asks for a signup, email, or download. Enter your numbers and the result updates instantly.

How accurate is this calculator?

It uses standard formulas and recalculates the moment you change a value, so the math is exact for the inputs you enter. Treat the result as a reliable planning estimate; for decisions with legal or tax consequences, confirm the figures with a qualified professional.

Does it work on my phone?

Yes. The calculator is mobile-friendly and works on any phone, tablet, or computer — there is no app to install and nothing to save.

Can I add this calculator to my own website?

Yes. Scroll to “Add this free calculator to your site” above and copy the embed snippet to place the live calculator on your blog or website for free.

Last reviewed: September 2026. Free to use, no signup — Amortization Calculator by ToolWise Digital.

Add this free calculator to your site

Copy the snippet to embed the live calculator on your blog or website — free for any site. The small “Calculator by ToolWise Digital” credit line keeps it free; you're welcome to remove it, but we appreciate you leaving it.

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