Equal payment vs equal principal?

Equal payment keeps the monthly amount constant; equal principal has a higher early payment but lower total interest.

What rate and term does this assume?

This page assumes 4.0% over 30 years (360 months), equal payment. Change the rate and term in the calculator.

Does early repayment reduce interest?

Yes — repaying principal early reduces the remaining interest, though early-repayment fees may apply.

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₩170,000,000 Loan Interest (4% / 30yr) - Toolkit

For a ₩170,000,000 loan at 4% over 30 years (equal payment), the monthly payment is about ₩811,606 and total interest about ₩122,178,160.

2026Equal-payment (amortizing) formula

Loan principal

Annual rate (%)

Loan term (months)

Grace period (months, optional)

Monthly payment (first month)811,606

Total payments292,178,160

Total interest122,178,160

Interest calculationShow steps

Total interest122,178,160

Total payments − principal

= 292,178,160 − 170,000,000

Repayment schedule (first 12 payments)

No.	Payment	Principal	Interest	Balance
1	811,606	244,939	566,667	169,755,061
2	811,606	245,756	565,850	169,509,305
3	811,606	246,575	565,031	169,262,730
4	811,606	247,397	564,209	169,015,333
5	811,606	248,222	563,384	168,767,111
6	811,606	249,049	562,557	168,518,062
7	811,606	249,879	561,727	168,268,183
8	811,606	250,712	560,894	168,017,471
9	811,606	251,548	560,058	167,765,923
10	811,606	252,386	559,220	167,513,537
11	811,606	253,228	558,378	167,260,309
12	811,606	254,072	557,534	167,006,237

Showing only the first 12 payments of the full term.

How it's calculated & notes

·With equal-payment repayment the monthly amount stays constant; with equal-principal repayment the principal portion is constant, so interest gradually decreases.
·During the grace period you pay interest only and the principal stays unchanged; after it ends, the principal is repaid over the remaining term. A longer grace period increases total interest.
·Actual loans may differ in total interest depending on prepayment fees, variable rates, and day-count conventions.
·This calculator provides an estimate assuming a fixed rate and equal monthly repayment.

Repayment Analysis for a ₩170,000,000 Loan

Borrowing ₩170,000,000 at 4% for 30 years (equal payment) gives a monthly payment of about ₩811,606, total interest of about ₩122,178,160, and total repayment of about ₩292,178,160.

Repayment summary

Monthly payment: ₩811,606
Total interest: ₩122,178,160
Total repayment: ₩292,178,160

What is the loan interest calculator?

The loan interest calculator computes the monthly payment and total interest from the principal, annual rate, and term. Equal payment keeps the monthly amount constant; equal principal repays a fixed principal each month, with a higher early burden but less total interest. This page assumes {rate}% over {years} years.

Repayment methods

Equal payment: same monthly amount
Equal principal: same principal, declining interest
Rate and term greatly affect total interest

View the full loan interest table →

Frequently Asked Questions

Equal payment vs equal principal?: Equal payment keeps the monthly amount constant; equal principal has a higher early payment but lower total interest.
What rate and term does this assume?: This page assumes 4.0% over 30 years (360 months), equal payment. Change the rate and term in the calculator.
Does early repayment reduce interest?: Yes — repaying principal early reduces the remaining interest, though early-repayment fees may apply.

Last updated: July 2026 · Sources: 한국은행