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Loan Repayment Calculator | Monthly Payment, Total Interest, and Plan Comparison

Estimate monthly payment, total interest, total repayment, and first-to-last payment differences for amortized and equal-principal loan repayment plans.

Finance
-Monthly payment (first)
-Total interest
-Total repayment
-Total payments

Repayment comparison

Amortized: - / Equal principal: first - → last -

Interest difference: -

Enter amount, rate, and term to calculate monthly payment and total interest. Amount is capped at 1 quadrillion KRW and term at 50 years.

Check loan payments before you talk to a lender

Before a loan consultation, the first questions are usually “How much will I pay each month?” and “How much interest will this cost overall?”

Enter the loan amount, annual interest rate, and repayment term to estimate monthly payments instantly, then compare amortized repayment with equal-principal repayment in one view.

Key features

  • Amortized and equal-principal repayment support
  • Equal-principal first and final monthly payments
  • Total interest and total repayment calculation
  • 100M KRW example, copy-ready result, and clear blank/range errors
  • Instant recalculation on mobile and desktop
  • 0% interest and edge-case handling

How to use

  1. Enter the loan amount, for example 100,000,000 KRW.
  2. Enter the annual interest rate, for example 4.2.
  3. Enter the repayment term in years and choose a repayment type, for example 30 years and amortized repayment.

As you type, the result cards show monthly payment, total interest, and total repayment. The calculator accepts amounts from 1 KRW to 1 quadrillion KRW, rates from 0% to 100%, and whole-year terms from 1 to 50 years.

Example

  • Loan amount: 100M KRW
  • Annual interest rate: 4.2%
  • Term: 30 years

With amortized repayment, you can review the estimated monthly payment, total interest, and total repayment at once. Switching to equal-principal repayment shows the higher first payment, lower final payment, and typically lower total interest.

FAQ

What is the difference between amortized and equal-principal repayment?

Amortized repayment keeps the monthly payment almost fixed. Equal-principal repayment pays the same principal each month, so the first payment is higher and the last payment is lower.

Why can the result differ from a bank quote?

Actual loans can include fees, day-count rules, preferential rates, prepayments, and product-specific rounding. Use this as a quick comparison before checking the official repayment table.

Can I calculate a 0% interest loan?

Yes. At 0% interest, the monthly payment is the principal divided by the number of months and total interest is zero.

Which numbers should I compare between repayment plans?

Compare the amortized monthly payment, the equal-principal first and final payments, and the total interest difference together. For the final month-by-month schedule, use the official repayment table from your lender.

Summary

This loan interest calculator helps you quickly estimate monthly payment, total interest, and total repayment before choosing or discussing a loan.

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