Car Loan Calculator
From the car price, down payment, trade-in, rate and term, compute the loan amount, monthly payment and total interest.
輸入資料
計算結果
供款走勢 (剩餘本金 / 累計利息)
每年本金與利息分佈
貸款額與總利息佔比
圖表解讀：如圖所示，等額本息還款下供款初期利息佔比最高、償還本金較少，隨剩餘本金逐年下降，利息佔比逐步縮小。年期拉長雖能降低每月供款，但「累計利息」曲線會顯著抬升——由於車輛折舊往往快過還款速度，年期過長時更易出現『欠款高於車值』，因此在現金流許可下應盡量縮短年期或提高首期。
重點速覽：Loan amount = car price - down payment - trade-in (floor at zero). Monthly payment is the amortised instalment on that loan; total interest = total paid - principal. A larger down payment or trade-in lowers the loan and thus the monthly payment and total interest.
計算公式
貸款額 = 車價 − 首期 − 舊車折抵。
每月供款採用等額本息 (年金) 公式：PMT = P × r ÷ (1 − (1 + r)^−n)，其中 P 為貸款額、r 為每月利率 (年利率 ÷ 12)、n 為總期數 (年期 × 12)。
總利息 = 每月供款 × 期數 − 貸款額。
$$\text{Loan} = \text{CarPrice} - \text{DownPayment} - \text{TradeIn}$$$$PMT = P \times \dfrac{r}{1 - (1+r)^{-n}}, \quad r = \dfrac{\text{annualRate}}{12}, \quad n = \text{years} \times 12$$$$\text{TotalInterest} = PMT \times n - P$$使用說明
- Enter the car price, down payment and trade-in value.
- Enter the annual interest rate and the loan term.
- View the loan amount, monthly payment and total interest.
不同利率與年期下的每月供款與總利息對照表
| 還款年期 | 年利率 3% | 年利率 5% | 年利率 7% |
|---|---|---|---|
| 3 年 | 月供 HK$6,979／總息 HK$11,262 | 月供 HK$7,193／總息 HK$18,949 | 月供 HK$7,411／總息 HK$26,778 |
| 5 年 | 月供 HK$4,312／總息 HK$18,749 | 月供 HK$4,529／總息 HK$31,746 | 月供 HK$4,752／總息 HK$45,137 |
| 7 年 | 月供 HK$3,171／總息 HK$26,380 | 月供 HK$3,392／總息 HK$44,940 | 月供 HK$3,622／總息 HK$64,268 |
以貸款額 HK$240,000 (車價 HK$30 萬、首期 HK$6 萬) 的每月供款計算，數字經等額本息公式實算，僅供參考，實際以貸款機構審批為準。
理財情境案例
年期抉擇：同一部車 3 年 vs 7 年，利息差逾 5 萬
以貸款額 HK$240,000、年利率 5% 為例：選 3 年期每月供 HK$7,193、總利息約 HK$18,949；選 7 年期每月供降至 HK$3,392，但總利息升至約 HK$44,940。
年期由 3 年拉長至 7 年，每月少供約 HK$3,801，短期現金流較鬆動，但整段還款期多付利息約 HK$25,991。年期越長、月供越低，但總利息越高，也更易出現『供款未完、車值已大幅折舊』的負資產風險。
首期威力：多付首期直接省息
車價 HK$30 萬、年利率 5%、5 年期。若首期 HK$6 萬 (貸款 HK$24 萬)，月供約 HK$4,529、總利息約 HK$31,746。
若把首期提高至 HK$10 萬 (貸款 HK$20 萬)，月供降至約 HK$3,774、總利息約 HK$26,455，單是多付 HK$4 萬首期便可節省約 HK$5,291 利息。首期越多、貸款額越低，利息成本與月供壓力都同步下降，但仍須保留足夠應急現金。
常見問題
How does the down payment affect the loan?
The down payment directly reduces the loan amount, so a larger down payment lowers both the monthly payment and the total interest. It is the most direct lever to cut financing cost and the lender's risk.
What does trade-in mean?
It is the value of your old car offset against the new car price, reducing the amount you need to borrow. It works like an extra down payment — the more trade-in value, the smaller the loan and the less interest.
Is the monthly payment the full cost of the car?
No. This is principal + interest only. The real cost also includes first registration tax, insurance, vehicle licence, maintenance and possible dealer/mortgage fees. Add these to compare with renting or buying with cash.
Car loan vs personal loan vs hire purchase?
A car loan is secured on the vehicle (usually lower rate). A personal loan is unsecured (often higher rate, more flexible). Hire purchase means you do not own the car until the final payment. Compare the APR, term, fees and ownership terms; the cheapest nominal rate is not always the cheapest overall.
Any Hong Kong notes on car finance?
Hong Kong car loans are commonly offered by banks and finance companies; watch the APR, handling fees and early-repayment terms. The car itself carries first registration tax, annual licence and insurance as separate costs. For a like-for-like comparison, use the effective annual rate and total cost of credit, and never borrow beyond your debt-servicing capacity (see the debt-to-income ratio).
相關工具
參考資料
內容審核：香港計算器財經團隊。計算邏輯採標準等額本息年金公式，首次登記稅資料參考運輸署（TD）及香港海關公佈之私家車稅率，理財原則參考投資者及理財教育委員會（IFEC）指引，結果僅供參考，實際以相關機構公佈為準。