Cost of Goods Sold (COGS) Calculator
From beginning inventory, purchases and ending inventory, compute COGS and the gross profit and margin.
輸入資料
計算結果
重點速覽：COGS = beginning inventory + purchases - ending inventory. It is the direct cost of goods actually sold — only costs you can trace to the product (materials, direct labour, freight-in, packaging); selling, admin and overhead are excluded. Then gross profit = revenue - COGS; gross margin = gross profit / revenue. Example: begin 50k + buy 200k - end 30k = COGS 220k. The inventory method (FIFO, weighted average, specific ID) changes COGS when prices move. WARNING: A wrong count distorts COGS, gross profit and tax. COGS is a deductible expense in computing Hong Kong Profits Tax. Education, not advice.
計算公式
銷貨成本 = 期初存貨 + 本期進貨 − 期末存貨。
$$\text{COGS} = \text{期初存貨} + \text{本期進貨} - \text{期末存貨}$$$$\text{毛利} = \text{營業額} - \text{COGS}$$使用說明
- Enter beginning inventory, purchases and ending inventory.
- Optionally enter revenue to see gross profit and margin.
- View the COGS, gross profit and gross margin.
期初存貨 HK$50,000、本期進貨 HK$200,000 (可供出售成本 HK$250,000) 時，不同期末存貨對應的 COGS
| 期初存貨 | 本期進貨 | 期末存貨 | 銷貨成本 (COGS) | 解讀 |
|---|---|---|---|---|
| HK$50,000 | HK$200,000 | HK$20,000 | HK$230,000 | 期末存貨低，賣出多、COGS高 |
| HK$50,000 | HK$200,000 | HK$40,000 | HK$210,000 | 存貨周轉正常 |
| HK$50,000 | HK$200,000 | HK$60,000 | HK$190,000 | 期末存貨高，滯銷、COGS低 |
| HK$50,000 | HK$200,000 | HK$80,000 | HK$170,000 | 積壓明顯，需留意呆滯 |
| HK$50,000 | HK$200,000 | HK$100,000 | HK$150,000 | 大量存貨未售出 |
理財情境案例
案例一：由 COGS 算出毛利與毛利率
一間零售店期初存貨 HK$50,000、本期進貨 HK$200,000、期末存貨 HK$40,000。COGS = 50,000 + 200,000 − 40,000 = HK$210,000。
若該期營業額為 HK$350,000，則毛利 = 350,000 − 210,000 = HK$140,000，毛利率 = 140,000 ÷ 350,000 × 100% = 40%。
結論：COGS 是毛利的起點。店主若能壓低進貨成本或減少滯銷 (降低 COGS)，在同樣售價下毛利率就能提升 — 40% 的毛利率是評估這門生意獲利能力的關鍵指標。
案例二：存貨計價方法影響 COGS 與毛利
物價上升時期，某商戶期初存貨 HK$80,000、本期進貨 HK$180,000。若用先進先出 (FIFO)，先賣舊 (便宜) 貨，期末留下的是新 (較貴) 貨，期末存貨估為 HK$100,000，COGS = 80,000 + 180,000 − 100,000 = HK$160,000。
若改用加權平均法，期末存貨估為 HK$60,000，COGS = 80,000 + 180,000 − 60,000 = HK$200,000。
結論：同樣進銷，FIFO 在物價上升時期末存貨較高、COGS 較低、帳面毛利較高;加權平均則相反。計價方法一經選定應一致沿用，跨公司比較毛利時也要留意雙方是否用相同方法。
常見問題
What costs are included in COGS?
Only direct, traceable-to-product costs: raw materials, direct labour to make/source the goods, inbound freight, and packaging. Selling, marketing, admin salaries, rent and depreciation are operating expenses, not COGS, and are taken below gross profit.
Why does ending inventory matter so much?
COGS = beginning + purchases - ending. A higher ending inventory means fewer goods counted as 'sold', so lower COGS and higher gross profit (and tax); a lower ending inventory does the opposite. So inventory accuracy directly drives reported profit and tax — a common audit focus.
How does the inventory method affect COGS?
When purchase prices change, FIFO (oldest costs first) and weighted average give different COGS. In rising prices, FIFO shows lower COGS and higher profit (more tax now); weighted average smooths it. The method must be consistent and is a key accounting choice.
Is COGS deductible for Hong Kong Profits Tax?
Yes. In computing assessable profits, the costs of goods sold (and other wholly and exclusively incurred business expenses) are generally deductible. Proper inventory records support the deduction. For specifics, follow the Inland Revenue Department and consult an accountant.
Gross profit vs gross margin — which to watch?
Gross profit is the absolute amount; gross margin is the percentage (gross profit / revenue), better for comparing across periods or with peers. A falling margin signals rising direct costs or weak pricing even if the profit figure looks fine. Track both.
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。