Car Depreciation Calculator
From the initial value and age, estimate the current resale value, total depreciation and the cumulative depreciation percentage.
輸入資料
計算結果
車值折舊曲線
圖表解讀：上表顯示汽車折舊『前快後慢』的典型曲線：以 HK$300,000 新車為例，頭一年就跌價約 HK$57,000 (19%),到第 5 年累積折舊高達 HK$180,000 (六成)。折舊最陡的是頭一兩年，這也是為何許多人認為買一至兩年車齡的二手車更划算。
重點速覽：Car depreciation estimates value lost over time. Using a declining-balance model (fixed % of remaining value each year, e.g. 15%): current value = initial x (1 - rate)^age; total depreciation = initial - current; depreciation % = total / initial x 100%. Example: HK$300,000 car at 15%/yr, 5y → value ≈ 300k x 0.85^5 ≈ HK$133,004, depreciation ≈ HK$166,996 (≈ 55.7%). In Hong Kong, first registration tax is paid on top and generally not recovered on resale, so the real loss is larger; EVs may hold value differently under the EV concession. WARNING: Estimate only; real resale depends on brand, mileage, condition, accident history, demand. Education, not advice.
計算公式
現時車值 = 新車購入價 × 該車齡的殘值百分比 (依折舊曲線線性內插)。
殘值曲線 (相對購入價)：購入瞬間 91%、1 年 81%、2 年 69%、3 年 58%、4 年 49%、5 年 40%，約 10.5 年歸零。
累積折舊 = 新車購入價 − 現時車值；折舊百分比 = 累積折舊 ÷ 新車購入價 × 100%。
$$現時車值：$V = P_0\times ResidualPct(age)$ (依折舊曲線線性內插)$$$$累積折舊：$Dep = P_0 - V$$$$$折舊百分比：$\dfrac{Dep}{P_0}\times100\%$$$使用說明
- Enter the initial car value (purchase price).
- Enter the car's age in years.
- View the estimated current value, total depreciation and percentage.
新車價 HK$300,000 下不同車齡的估算車值 (依折舊曲線)
| 車齡 | 殘值率 | 現時估算車值 (HK$) | 累積折舊 (HK$) | 折舊百分比 |
|---|---|---|---|---|
| 1 年 | 81% | 243,000 | 57,000 | 19% |
| 2.5 年 | 63.5% | 190,500 | 109,500 | 36.5% |
| 3 年 | 58% | 174,000 | 126,000 | 42% |
| 5 年 | 40% | 120,000 | 180,000 | 60% |
理財情境案例
案例一：三年車齡的車還值多少
某人三年前以 HK$300,000 購入新車，想估算現時車值。依折舊曲線，3 年車齡的殘值率約 58%。
現時估算車值 = 300,000 × 58% = HK$174,000；累積折舊 = 300,000 − 174,000 = HK$126,000；折舊百分比 = 126,000 ÷ 300,000 = 42%。
解讀：短短三年，這部車已折舊了 42%、跌價 HK$126,000，現值約 HK$174,000。這清楚呈現了『汽車是消耗品』的本質——折舊是持有汽車最大的隱藏成本，遠超油費、保養等日常開支。轉售前先了解合理車值，能避免被壓價或對車價有不切實際的期望。
案例二：頭一年 vs 第五年的折舊落差
同樣一部 HK$300,000 的車，比較第 1 年與第 5 年的車值。第 1 年殘值率約 81%,車值 = 300,000 × 81% = HK$243,000 (累積折舊 HK$57,000、19%);第 5 年殘值率約 40%,車值 = 300,000 × 40% = HK$120,000 (累積折舊 HK$180,000、60%)。
頭一年折舊約 HK$57,000，而到第五年累積折舊已達 HK$180,000。
解讀：折舊速度並不平均——新車落地頭一兩年跌得最兇 (一年就蒸發近兩成價值),之後才逐漸放緩。這正是『買新車 vs 買二手車』的核心考量：買新車要承受最陡的初期折舊，而買一至兩年車齡的二手車，等於讓上一手車主替你吃掉了最貴的那段折舊。實際折舊會因品牌、車型、里程與車況而異，本結果僅供參考。
常見問題
Why does value drop fastest early?
Because the model takes a fixed percentage of the remaining value each year (declining balance). A new car loses a big chunk the moment it is titled and driven off, then the annual dollar loss shrinks as the base falls. So year one is the steepest; later years lose less in absolute terms even at the same rate.
Does the first registration tax come back on resale?
Generally no. In Hong Kong, first registration tax is paid on top of the car price at purchase and is not recovered when you sell. So the buyer's total outlay (car + tax + licence + insurance) is much higher than the resale value, and the true economic loss is the depreciation plus the non-recoverable tax. Factor this into total cost of ownership.
How accurate is the estimate?
It is a rough benchmark. Actual resale depends on brand and model popularity, mileage, maintenance and condition, accident history, colour/options, and market supply/demand. Use it for planning and a sanity check, then confirm with used-car listings or a professional appraisal before a real deal.
Do electric vehicles depreciate differently?
They can. EV resale is influenced by battery health, range, charging access and the prevailing first registration tax concession (which changes over time). Some EVs hold value well, others depreciate fast as tech improves. Treat the rate as a starting point and adjust for the specific model and policy.
How do I use this for total cost of ownership?
Combine depreciation with finance interest, first registration tax, licence, insurance, fuel/electricity and parking to get the true annual cost of owning the car. A cheap purchase price can still be expensive if depreciation and tax are high. Pair with the car affordability and car loan calculators.
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。