Certificate of Deposit (CD) Calculator
From principal, annual rate, term and compounding frequency, compute the CD maturity balance and interest earned.
輸入資料
計算結果
重點速覽：CD / Time Deposit locks cash for a fixed term for a higher rate than a savings account. final balance = principal x (1 + r/m)^(m·t), r = annual rate, m = compounding per year, t = years; interest = final balance - principal. Example: HK$100,000 at 4% monthly, 1y → ≈ HK$104,074, interest ≈ HK$4,074. WARNING: Enter the nominal annual rate, not APY (APY double-counts compounding). Early withdrawal usually forfeits interest and may incur a penalty. For HK personal depositors, deposit interest is generally not subject to HK profits/salaries tax, and deposits are protected by the Deposit Protection Scheme (DPS) up to the per-depositor-per-bank limit. Education, not advice.
計算公式
到期最終結餘 FB = ID × (1 + r/m)^(m·t)。
其中 ID 為初始存款、r 為年利率、m 為每年複利次數、t 為年期。
所賺利息 = 到期最終結餘 − 初始存款。
$$到期最終結餘：$FB = ID\left(1+\dfrac{r}{m}\right)^{mt}$$$$$所賺利息：$Interest = FB - ID$$$$$示例 (10 萬、4%、每月、1 年)：$100000\times\left(1+\frac{0.04}{12}\right)^{12}\approx104074$$$使用說明
- Enter the initial deposit.
- Enter the bank's annual rate and the term.
- Pick the compounding frequency to see the maturity balance and interest.
初始存款 HK$100,000、年利率 4% 下的到期結餘與利息
| 年期 | 複利頻率 | 到期結餘 (HK$) | 所賺利息 (HK$) |
|---|---|---|---|
| 1 年 | 每年 (1 次) | 104,000.00 | 4,000.00 |
| 1 年 | 每月 (12 次) | 104,074.15 | 4,074.15 |
| 3 年 | 每月 (12 次) | 112,727.19 | 12,727.19 |
理財情境案例
案例一：一筆定期存款的到期收益
某人把 HK$100,000 做 3 年定期存款，年利率 4%,每月複利。
到期結餘 = 100,000 × (1 + 0.04/12)^(12×3) ≈ HK$112,727.19；所賺利息 = 112,727.19 − 100,000 ≈ HK$12,727.19。
解讀：把 10 萬元鎖定 3 年，到期連本帶利約 11.27 萬，賺得利息約 HK$12,727。定期存款的最大特點是『本金與利率在存期內鎖定』,不受市場波動影響，適合不急用、想要穩定利息收入的資金；代價是資金流動性較低。
案例二：複利頻率造成的差異
同樣 HK$100,000、年利率 4%、存 1 年，比較每年複利與每月複利。每年複利：100,000 × (1 + 0.04)^1 = HK$104,000，利息 HK$4,000。每月複利：100,000 × (1 + 0.04/12)^12 ≈ HK$104,074.15，利息約 HK$4,074.15。
每月複利比每年複利多賺約 HK$74。
解讀：複利頻率越高，利息越早滾入本金再生息，到期收益略高，但差距通常不大。比較不同定期產品時，除了看標示年利率，最好連複利方式一併換算成年度百分比收益率 (APY) 再比較，才算公平。⚠️ 香港部分高息定期常設有『新資金』『指定存期』等條件，實際利率與到期收益以銀行公佈為準。
常見問題
What is the difference between a CD and a savings account?
A time deposit locks the money for a fixed term at a usually higher rate; early withdrawal typically forfeits part or all of the interest and may incur a penalty. Longer terms and larger amounts usually get better rates. It is the trade of liquidity for yield.
Should I enter the annual rate or the APY?
Enter the bank's quoted nominal annual rate and choose the compounding frequency yourself. Do NOT enter the APY (which already includes compounding), or you will double-count and overstate the return.
Does compounding frequency affect the return?
Yes. At the same nominal rate, more frequent compounding (e.g. daily) gives a slightly higher maturity balance than annual compounding, because interest is added to principal more often.
Can I withdraw before maturity, and what happens?
Usually yes, but at a cost — typically you lose part or all of the interest (perhaps only earning a low savings rate) and may pay an early-withdrawal fee; some products do not allow partial withdrawal. Tips: only lock idle funds you will not need; read the early-withdrawal terms; consider laddering (split into several terms) so you only break one if cash is needed; note some banks offer slightly more flexible products at a lower rate. This calculator shows the hold-to-maturity return; actual early-withdrawal results follow the bank's terms.
Is Hong Kong deposit interest taxable, and is it protected?
Two common questions. Tax: Hong Kong's regime is simple — interest earned by an individual from a Hong Kong bank deposit is generally NOT subject to profits tax or salaries tax (Hong Kong has no general interest tax or capital gains tax); this is for ordinary individual depositors, special circumstances may differ — consult a tax professional or the IRD. Protection: Hong Kong has the Deposit Protection Scheme (DPS) administered by the Deposit Protection Board, compensating eligible deposits (including time deposits) if a member bank fails, up to a per-depositor-per-bank limit (the limit is reviewed from time to time — check the official figure). Practical tips: confirm your bank is a DPS member; if deposits are large, spread across banks to stay within each limit; check the latest scope and limit. ⚠️ Rules change; this is general reference only — follow the IRD and DPS official publications.
相關工具
參考資料
內容審核：香港計算器財經團隊。計算邏輯與公式參考香港金融管理局（HKMA）及投資者及理財教育委員會（IFEC）之個人理財計算指引，結果僅供參考，實際以相關機構公佈為準。