Phần hướng dẫn bên dưới chưa có bằng tiếng Việt nên được hiển thị bằng tiếng Anh. Bản thân máy tính đã được dịch đầy đủ.
Cách sử dụng máy tính này
- Enter your initial deposit and how much you'll add each month.
- Enter the annual interest rate and how often it compounds.
- Optionally enter your tax rate on interest income and an expected inflation rate.
- Compare the nominal ending balance with its value in today's money.
Công thức
Interest compounds at the chosen frequency and monthly deposits are added at the end of each month. Tax is approximated by reducing the rate to r × (1 − tax rate). The value in today's money divides the ending balance by cumulative inflation.
After-tax rate = r × (1 − tax)
Real value = Balance / (1 + inflation)^t
Example
- $5,000 initial deposit plus $100 per month at 4.5% compounded monthly for 5 years.
- Contributions total $11,000 and the ending balance is about $12,982.
- With 3% inflation, that balance is worth about $11,198 in today's money.
Câu hỏi thường gặp
Why adjust for inflation?
Inflation reduces purchasing power. If your interest rate after tax is below inflation, your savings lose real value even as the balance grows.
How is interest income taxed?
Rules vary by country and account type. Many tax-advantaged accounts are exempt. This calculator applies a flat rate to interest as it is earned, which is an approximation.
What's the difference between APY and interest rate?
APY (annual percentage yield) includes the effect of compounding. A 4.5% rate compounded monthly equals an APY of about 4.59%.