Loan Interest Calculator
Estimate monthly loan payments, total interest, and early amortization rows across equal-payment, equal-principal, and bullet repayment structures.
Repayment method
Typical monthly payment
298만 / monthTotal interest
741만Total repayment
1억 741만Early repayment schedule
Shows the first 12 months of principal and interest flow.
| Month | Payment | Principal | Interest | Balance |
|---|---|---|---|---|
| 1 | 298만 | 259만 | 39만 | 9,741만 |
| 2 | 298만 | 260만 | 38만 | 9,481만 |
| 3 | 298만 | 261만 | 37만 | 9,219만 |
| 4 | 298만 | 262만 | 36만 | 8,957만 |
| 5 | 298만 | 263만 | 35만 | 8,694만 |
| 6 | 298만 | 264만 | 34만 | 8,430만 |
| 7 | 298만 | 265만 | 33만 | 8,164만 |
| 8 | 298만 | 266만 | 32만 | 7,898만 |
| 9 | 298만 | 267만 | 31만 | 7,630만 |
| 10 | 298만 | 268만 | 30만 | 7,362만 |
| 11 | 298만 | 270만 | 29만 | 7,092만 |
| 12 | 298만 | 271만 | 28만 | 6,822만 |
How to use this result
Loan comparisons are rarely about one interest rate alone. The repayment method, grace period, and term shape the monthly cash burden as much as the APR does.
This calculator is meant for first-pass scenario testing. It helps compare installment structures before checking the exact lender product sheet, fees, and approval conditions.
Real execution amounts may differ because lenders apply day-count conventions, fees, mid-term prepayment rules, insurance, and product-specific rounding standards.
Examples
Home appliance loan
Grace-period business loan
Bullet repayment review
Common questions
Q.Is this an official lender quote?
No. It is a directional estimate for planning and comparison only.
Q.Why does equal-principal start higher?
Because the principal portion is fixed while interest is highest at the beginning when the balance is largest.
Q.Can I rely on this for a contract decision?
Use it as a comparison tool, then confirm the final repayment schedule with the actual lender before signing.
Before using Loan Interest
When it helps
Loan Interest is useful when dates, time, money, interest, tax, and planning numbers need a quick first-pass estimate. It is designed for situations like turning 1,000만 원, 연 4.7%, 36개월 into 월 상환액과 총 이자 비교 without leaving the browser workflow.
Suggested workflow
The basic workflow is simple: enter Loan amount and annual rate, adjust Term and grace period when needed, and review Typical monthly payment. Before relying on the result, check the units, date, file type, rounding basis, or other assumptions that may change the outcome.
How to verify results
Loan Interest is a supporting utility for quick judgment. If the result affects contracts, filings, payments, security, customer data, or other important decisions, verify it against official sources, source systems, internal policy, or qualified review.
Data handling notice
Reference calculation: this tool provides quick estimates from your inputs and common public formulas.
No server storage: calculation inputs are only used to display the result and are not stored by ZHS.
Verification required: legal, tax, payroll, real-estate, or financial decisions require current official sources and expert review.