Days Sales Outstanding (DSO) Calculator
From accounts receivable and credit sales, compute how many days it takes to collect payment (DSO).
輸入資料
計算結果
重點速覽：DSO = accounts receivable / credit sales x period days (365 for a year). It shows the average days to collect after a credit sale. Lower = faster collection, better cash flow; higher = slow collection, bad-debt/cash risk. Use credit sales (not total). WARNING: compare within industry, watch seasonality/terms. Education, not advice.
計算公式
DSO = 應收帳款 ÷ 賒銷收入 × 期間天數。
$$DSO = \dfrac{\text{應收帳款}}{\text{賒銷收入}} \times \text{期間天數}$$$$CCC = DSO + DIO - DPO$$使用說明
- Enter accounts receivable at period end.
- Enter credit sales for the period (exclude cash).
- Enter the period days (365 for a year) for DSO.
年賒銷收入固定為 HK$3,650,000 (365 天) 時，不同應收帳款對應的 DSO
| 應收帳款 | 年賒銷收入 | 應收帳款周轉天數 (DSO) | 解讀 |
|---|---|---|---|
| HK$250,000 | HK$3,650,000 | 25 天 | 收款快，現金回流佳 |
| HK$375,000 | HK$3,650,000 | 37.5 天 | 偏健康 |
| HK$500,000 | HK$3,650,000 | 50 天 | 中等，常見信用期水平 |
| HK$625,000 | HK$3,650,000 | 62.5 天 | 偏長，留意催收 |
| HK$750,000 | HK$3,650,000 | 75 天 | 收款慢，資金佔用大 |
理財情境案例
案例一：由 DSO 看收款效率
一家 B2B 供應商年賒銷收入 HK$3,650,000，應收帳款 HK$500,000。DSO = 500,000 ÷ 3,650,000 × 365 = 50 天，代表平均約 50 天才收回一筆賒帳。
若公司給客戶的信用期是 30 天，實際 DSO 卻達 50 天，代表有不少客戶超期付款，催收或授信管理有改善空間。
結論：DSO 與帳面信用期的差距，是判斷收款紀律的實用信號 — 差距越大，資金被拖欠的情況越嚴重。
案例二：收緊信用條款縮短 DSO
一家公司原本應收帳款 HK$750,000、DSO = 75 天，現金常見緊絀。管理層透過提供提早付款折扣、加強催收、對高風險客戶收緊授信，把應收帳款降到 HK$375,000。
新的 DSO = 375,000 ÷ 3,650,000 × 365 = 37.5 天，收款時間縮短一半，釋放約 HK$375,000 的營運資金。
結論：縮短 DSO 能直接降低現金轉換週期、改善現金流，但要拿捏分寸 — 條款過嚴可能流失客戶，需在收款效率與銷售之間平衡。
常見問題
What is DSO and how is it computed?
DSO = accounts receivable / credit sales x period days (365 for a year). Example: AR 2,000,000, annual credit sales 12,000,000, 365 days → (2,000,000/12,000,000)x365 ≈ 60.8 days. It tells how long, on average, you wait to collect.
Why use credit sales, not total sales?
Because cash sales collect instantly and should not inflate the 'collection period'. Mixing them understates DSO. If credit sales aren't available, estimate or use total sales with a caveat — but prefer credit sales for accuracy.
Is a lower DSO always better?
Generally yes for cash flow, but not absolutely. Too aggressive collection may annoy customers or lose sales to lenient competitors. The goal is DSO near your credit terms (e.g. net 60) — far above signals collection problems; far below may mean overly strict terms hurting growth.
What are the Hong Kong SME implications and caveats?
HK SMEs often rely on credit sales to win clients but then face cash-flow pressure from slow collection; high DSO strains operations and may need factoring or financing. The HKTDC and HKPC advise tightening credit checks and terms. Caveats: (1) use credit not total sales; (2) compare within industry; (3) watch seasonality; (4) large one-off receivables distort. Education, not advice.
How does DSO relate to the cash conversion cycle?
CCC = DIO + DSO - DPO. DSO is the days receivables are outstanding — part of the 'money tied up' before you collect. Lower DSO shortens the cycle and frees cash. Together with DIO (inventory days) and DPO (payables days), managing all three optimises working capital. Use the cash-conversion-cycle calculator to see the combined effect.
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。