See how long cash is tied up in inventory and receivables.
Use balances and activity amounts that correspond to the selected period. One shared period applies to DIO, DSO and DPO. Currency labels do not convert values.
Zero or positive days. Comparison can be above, below or on target.
Zero or positive days. A zero previous value has no relative percentage change.
Your inputs remain local to this page.
42.7 days
Inventory Days / DIO
Estimated average number of days inventory remains before being sold.
Planning calculations based on entered accounting values. Cash-release figures are estimated working-capital release proxies, not guaranteed or immediately available cash.
All downstream calculations use unrounded values. Displayed intermediate values are rounded.
See how long cash is tied up in inventory and receivables. Calculate DIO, DSO, DPO and cash conversion cycle, then model inventory-day improvements.
Start in Inventory Days with beginning and ending inventory, cost of goods sold and a period of 30, 90, 365 or custom days. Enter balances and activity for one consistent accounting period. Optional user targets and previous-period values provide comparisons. Cash Conversion Cycle adds receivables and supplier-payment timing; What If? models reducing inventory days. Copy Results includes the active calculation and its assumptions. Reset restores the inventory fixture and clears all optional values and scenarios.
DIO measures inventory holding time. DSO measures receivables collection time. They are different working-capital metrics. Average inventory = (beginning inventory + ending inventory) / 2. DIO = average inventory / COGS × period days. This estimates the average number of days inventory remains before being sold. Use inventory at cost on a basis consistent with COGS. Two endpoint balances are a simplified average; frequent balances can better capture fluctuations.
Inventory turnover during this period = COGS / average inventory. For 365 days this is annual turnover. Annualized turnover = period turnover × 365 / period days. A 90-day ratio is labeled period turnover, with a separate annualized figure; annualization is a constant-rate extrapolation rather than a forecast. If average inventory is zero, DIO is zero with positive COGS, while turnover is undefined rather than infinite.
DSO = accounts receivable / credit sales × period days. It estimates the average number of days receivables remain outstanding. Credit sales excludes cash sales; use total sales only if all sales were on credit. This V1 accepts one receivables balance and labels it a point-in-time approximation; a representative average balance can be entered if available. DSO does not measure how quickly inventory sells.
Average AP = (beginning accounts payable + ending accounts payable) / 2. DPO = average AP / supplier-cost basis × period days. It estimates supplier-payment timing. Purchases is the preferred basis, using purchases corresponding to trade payables, preferably on credit. COGS proxy is an explicit approximation when purchases are unavailable; purchases and COGS need not match because of inventory movements and cost composition. Invalid or missing payables data does not silently become zero.
Operating cycle = DIO + DSO. It combines inventory holding time with receivables collection time. Explicitly selecting No — operating cycle only excludes payables. The calculator then labels the result Operating cycle and does not present it as full CCC.
CCC = DIO + DSO − DPO. The cash conversion cycle estimates how long operating cash remains tied up after supplier-payment timing is considered. All three components use the same selected period. This is a ratio-based planning measure, not a guaranteed date when money returns. A negative cash conversion cycle can occur when supplier-payment timing extends beyond the combined inventory and receivables cycle; the result is supported without a universal good or bad label.
The timeline follows Inventory → Sale / Invoice → Receivable → Cash. Inventory occupies DIO days and receivables occupy DSO days. Supplier terms contribute a −DPO financing offset. Text beside the visual states the same components and arithmetic. It is a simplified accounting sequence, not a calendar of actual invoice or payment events.
Average daily COGS = COGS / period days. Days reduced = current DIO − target DIO. Estimated reduction in average inventory investment = average daily COGS × days reduced. What If? accepts a target from zero to current unrounded DIO through a numeric field and a slider. This working-capital release proxy assumes inventory investment falls proportionally with holding days; it does not guarantee immediate cash availability. Actual effects can vary with purchasing timing, demand, margins, write-downs, seasonality, supplier terms, inventory mix and growth.
When considering a lower inventory-days target, compare a separate safety-stock and reorder-point estimate from demand and lead-time assumptions. This DIO model does not establish a safe stock level or guarantee service availability.
Target variance = actual days − your target days. Positive means above target; negative means below target; zero means on target. Optional targets for DIO and DSO have no universal recommended default. Previous-period change = current days − previous days. Relative change = (current − previous) / previous × 100. If previous days are zero, relative change is unavailable; absolute change still displays. Comparisons use unrounded values and neutral language. DIO and DSO vary by industry, business model, seasonality, payment terms and inventory strategy, so this calculator supplies no benchmark grading.
Period: 365 days. Beginning inventory $400,000.00; ending inventory $500,000.00; COGS $3,850,000.00. Average inventory = (beginning + ending) / 2 = $450,000.00. DIO = $450,000.00 / $3,850,000.00 × 365 = 42.6623 days (display 42.7). Inventory turnover = 8.56× during this annual period.
Period: 365 days. Beginning inventory $400,000.00; ending inventory $500,000.00; COGS $3,850,000.00. Average inventory = (beginning + ending) / 2 = $450,000.00. DIO = $450,000.00 / $3,850,000.00 × 365 = 42.6623 days (display 42.7). Inventory turnover = 8.56× during this annual period.
DSO = accounts receivable $320,000.00 / credit sales $3,750,000.00 × 365 = 31.1467 days (display 31.1).
Period: 365 days. Beginning inventory $400,000.00; ending inventory $500,000.00; COGS $3,850,000.00. Average inventory = (beginning + ending) / 2 = $450,000.00. DIO = $450,000.00 / $3,850,000.00 × 365 = 42.6623 days (display 42.7). Inventory turnover = 8.56× during this annual period.
DSO = accounts receivable $320,000.00 / credit sales $3,750,000.00 × 365 = 31.1467 days (display 31.1).
Beginning AP $300,000.00; ending AP $320,000.00; average AP $310,000.00. DPO = average AP / purchases $4,000,000.00 × 365 = 28.2875 days. Operating cycle = DIO + DSO = 73.8090 days. CCC = 42.6623 + 31.1467 − 28.2875 = 45.5215 days; each component is unrounded in the engine.
Period: 365 days. Beginning inventory $400,000.00; ending inventory $500,000.00; COGS $3,850,000.00. Average inventory = (beginning + ending) / 2 = $450,000.00. DIO = $450,000.00 / $3,850,000.00 × 365 = 42.6623 days (display 42.7). Inventory turnover = 8.56× during this annual period.
Actual DIO 42.7; target 35.0. 7.7 days above target.
Period: 365 days. Beginning inventory $400,000.00; ending inventory $500,000.00; COGS $3,850,000.00. Average inventory = (beginning + ending) / 2 = $450,000.00. DIO = $450,000.00 / $3,850,000.00 × 365 = 42.6623 days (display 42.7). Inventory turnover = 8.56× during this annual period.
Current DIO 42.6623; target 30.0 days. Days reduced = 12.6623. Average daily COGS = $3,850,000.00 / 365 = 10,547.9452. Estimated reduction in average inventory investment = unrounded daily COGS × unrounded days reduced = $133,561.64. This is a planning proxy, not guaranteed cash.
Balances must be zero or positive; COGS, credit sales when requested, and the chosen supplier-cost basis must be greater than zero. Monetary inputs and optional comparison days are limited to 1 trillion; numeric strings to 32 characters. Period days is a whole number 1–3,660. What-if target days cannot exceed current raw DIO. Nonfinite results or combined magnitudes above 1 quadrillion are rejected. A zero average inventory yields zero DIO and undefined turnover. Unusual negative accounting adjustments are outside this model.
All balances and activity amounts must correspond to one selected accounting period and use consistent currency and valuation bases. Currency selection changes the symbol only; no FX conversion occurs. DIO/DSO/DPO/CCC display one decimal; turnover two; money two where useful; percentage changes one. Tiny nonzero values retain additional digits so display rounding does not silently show zero. All downstream arithmetic uses full precision.
Invalid active inputs remove the current mode’s results and disable copy; inactive optional metrics are not required for inventory-only calculations. No DPO calculation is inferred from incomplete fields. Only explicit payables exclusion produces the operating cycle instead of CCC. Inputs stay in this page; there are no accounts, saved company records, URL-state persistence, accounting integrations or network calculations. Sources explain accounting relationships and do not endorse BuzCalculator.
For a separate shipping question, estimate density for a packaged shipment from actual packed dimensions and weight. Inventory value, DIO and DSO do not determine freight density, final classification or replenishment requirements.
Average beginning and ending inventory, divide by COGS, then multiply by the number of days in the same period.
DIO measures inventory holding time in days. Period turnover measures how many times COGS covers average inventory during the entered period; annualized turnover uses a disclosed 365-day basis.
DSO estimates receivables collection time: accounts receivable divided by credit sales, multiplied by period days. It is distinct from inventory holding time.
DPO estimates supplier-payment timing: average accounts payable divided by purchases, multiplied by period days. An explicitly selected COGS proxy is an approximation.
Add DIO and DSO, then subtract DPO. A negative value is mathematically valid when supplier-payment timing exceeds the combined holding and collection cycle.
Operating cycle equals DIO plus DSO. Cash conversion cycle subtracts DPO as a supplier-financing offset. Excluding payables leaves the operating cycle.
No universal threshold applies here. Industry, business model, seasonality, payment terms and inventory strategy affect interpretation. Compare your targets or a consistent previous period.
Enter your target inventory days in the optional comparison section. The calculator displays the unrounded actual-minus-target difference as above, below or on target.
It multiplies daily COGS by the reduction from current DIO to your target. This estimates a reduction in average inventory investment, not guaranteed immediately available cash.
Each ratio relates balances to activity over a period. Mixing periods makes the combined cycle inconsistent. One shared period controls all metrics in this calculator.
Accounting model and sources reviewed 2026-10-04. ACCA explains credit-sales and supplier-purchases bases, including approximation when purchases are unavailable. CFI explains the inventory, payable averages and operating/cash-cycle relationships. BuzCalculator’s what-if proxy follows algebraically from its DIO formula; it is a product scenario, not a source-endorsed cash forecast.