🪙 Korean Deposit & Installment Savings Interest Calculator (After-Tax)
Choose 예금 (a lump-sum time deposit) or 적금 (installment savings you pay into monthly), then enter your principal or monthly deposit, annual rate and term. It instantly shows the interest you actually receive after Korea's 15.4% interest-income tax (14% income + 1.4% local): pre-tax interest, the tax withheld, after-tax interest, and the maturity payout (principal + after-tax interest). Pick simple or monthly-compound. If your yearly interest and dividend income exceeds ₩20 million you may fall under comprehensive financial income taxation — the calculator flags this.
Savings details
Private by design. This tool runs entirely in your browser — nothing you enter is uploaded or stored, and it works offline.
About
In Korea, interest paid on bank deposits and savings is subject to a 15.4% withholding tax — 14% interest-income tax plus a local income tax equal to 10% of that (1.4%). For most savers whose yearly interest and dividend income is ₩20 million or less, this withholding settles the tax (separate taxation), so the after-tax figure this tool shows is what actually lands in your account. Above the ₩20 million threshold, the excess is combined with your other income and taxed at 6–45% progressive rates (comprehensive financial income taxation). Every calculation runs entirely in your browser — nothing you type is uploaded.
How to use
- Pick 예금 (deposit) or 적금 (installment savings), then enter the principal — or, for 적금, your monthly deposit — in won (₩).
- Set the annual interest rate (%) from your product terms.
- Enter the term, pick months or years, and choose simple or monthly-compound interest.
- Read the results: pre-tax interest, 15.4% tax withheld, after-tax interest, and maturity payout.
- Use 'Copy summary' to save the numbers, and watch for the comprehensive-tax notice if the interest is large.
FAQ
- How much tax is taken from deposit interest in Korea?
- 15.4% is withheld — 14% interest-income tax plus 1.4% local income tax (10% of the income tax). So you receive about 84.6% of the pre-tax interest.
- What is the ₩20 million comprehensive taxation threshold?
- If your total yearly interest and dividend income is ₩20 million or less, the 15.4% withholding settles it (separate taxation). Above ₩20 million, the excess is added to your other income and taxed at 6–45% progressive rates.
- Does it support simple and compound interest?
- Yes. Choose 'Simple' for lump-sum simple interest, or 'Monthly compound' to compound the interest each month over the term.
- Does it calculate 적금 (installment savings), not just 예금?
- Yes. Switch 'Savings type' to 적금 (installment savings) and enter your monthly deposit. Each month's deposit earns interest for its remaining term (simple), or compounds monthly, then the same 15.4% tax applies and you see the maturity payout on your total deposits.
- Is my financial data private?
- Yes. Everything is calculated locally in your browser. Nothing you enter is uploaded or stored on any server.