Deposit interest
The simple deposit model uses principal × annual rate × term. A 10,000,000 deposit at 4% for one year produces about 400,000 pre-tax interest; six months produces roughly half because the money earns interest for half the time.
073 · BUSINESS & FINANCE
Deposit & Savings Calculator
Calculate total principal, estimated interest, and maturity amounts for deposits and installment savings with pre-tax and reference after-tax values.
LOCALCALCULATE IN YOUR BROWSER
LOCALAmounts and results are calculated only in this browser and are not sent to or stored on a server.
Uses a simple-interest reference where the full principal is deposited for the selected term.
Annual Interest Rate3%
Term12 Months
Reference Tax Rate0%
Display settings
RESULT · Calculation result
DepositTotal Principal10,000,000KRW
Pre-tax Interest300,000KRW
Pre-tax Maturity10,300,000KRW
Reference After-tax Interest300,000KRW
Reference After-tax Maturity10,300,000KRW
Formula
interest = principal × 3/100 × 12/12REFERENCE · After-tax values apply only the reference tax rate you enter to the interest. Product-specific preferential rates, compounding, early-withdrawal rules, and actual taxation are not determined.
HOW TO USE
How to use
- 01
Choose Deposit or Installment Savings.
- 02
Enter principal for a deposit or the monthly contribution for savings.
- 03
Enter the annual interest rate and term in months or years.
- 04
Optionally enter a reference tax rate under Display settings.
- 05
Review total principal, pre-tax interest, pre-tax maturity, reference after-tax interest, and reference after-tax maturity, then copy the summary.
- 06
When reviewing after-tax interest, confirm that the product’s interest-payment method and tax treatment match the calculation assumptions.
INTEREST GUIDE
Deposit and savings interest
A deposit puts the full principal to work from the start, while installment savings add money over time. That difference in interest-bearing periods explains why the same headline rate can produce different interest.Savings interest
Installment contributions do not all earn interest for the full term. Earlier deposits earn for longer and later deposits for less time, so applying the annual rate to the entire accumulated principal would overstate interest.
Rate comparison
Compare the deposit pattern and term together with the advertised annual rate. A lump-sum deposit and monthly savings plan can produce different outcomes at the same rate, and preferential rates may apply only when conditions are met.
Pre-tax and after-tax
The after-tax reference applies the entered tax rate to interest, not to principal. Actual tax treatment, exemptions and preferential tax rules can vary by product and customer eligibility.
Early withdrawal
Many products apply a separate early-withdrawal rate if the account is closed before maturity. If you may need the money early, compare withdrawal conditions as well as the highest advertised rate.
What to compare
Do not compare maturity amount alone. Separate total principal, pre-tax interest, after-tax reference interest, contribution pattern and preferential-rate conditions. This calculator compares entered assumptions; it does not fetch a bank’s guaranteed payout.
IMPORTANT NOTES
Important notes
- The deposit calculation in TOOL073 is a simple-interest reference; compounding belongs to TOOL074.
- Installment savings reflect different deposit timing instead of treating all payments as if they were deposited on day one.
- Terms are normalized to months, so 12 months and 1 year are equivalent.
- Reference after-tax values apply the user-entered reference tax rate only to pre-tax interest.
- Product-specific preferential rates, compounding rules, early-withdrawal terms, and actual taxation are not determined.
- The same annual rate can produce different interest for deposits and installment savings because the money is deposited for different lengths of time.
- Deposits and installment savings can earn different interest at the same rate because each contribution remains invested for a different length of time.
FAQ
Frequently asked questions
01Why do deposits and installment savings earn different interest at the same rate?+
Savings contributions enter over time, so each payment earns interest for a different period.
02What is the total principal for 500,000 per month for 12 months?+
The total principal is 6,000,000.
03Is the reference after-tax value my actual payout?+
No. It only applies the reference tax rate you enter to the calculated interest.
04Does this calculator support compounding?+
TOOL073 focuses on simple deposit and monthly savings references; compounding, extra contributions, and goal amounts belong to TOOL074.
05Does it automatically fetch bank rates?+
No. It calculates only from the rate you enter.