Inventory Turnover Calculator
Measure how many times a business sells and replaces its inventory within a period. Use it to assess operational efficiency, benchmark against industry peers, or spot slow-moving stock.
About this calculator
Inventory turnover ratio measures how efficiently a company converts its inventory into sales. A high ratio indicates strong sales or lean inventory management; a low ratio may signal overstocking, weak demand, or obsolete goods. The formula is: Inventory Turnover = Cost of Goods Sold (COGS) / Average Inventory Value. COGS is used rather than revenue because both COGS and inventory are measured at cost, making the comparison apples-to-apples. Average inventory is typically calculated as (beginning inventory + ending inventory) / 2 for the period. You can also derive Days Inventory Outstanding (DIO) from this ratio: DIO = 365 / Inventory Turnover, which tells you how many days inventory sits before being sold. Benchmarks vary widely by industry — grocery retailers may turn inventory 20+ times per year, while jewelry stores may turn it fewer than 2 times.
How to use
A clothing retailer reports COGS of $480,000 for the year. Beginning inventory was $60,000 and ending inventory was $100,000, so average inventory = ($60,000 + $100,000) / 2 = $80,000. Step 1 — Divide COGS by average inventory: $480,000 / $80,000 = 6.0. The inventory turnover ratio is 6, meaning the retailer sold and replaced its inventory 6 times during the year. Step 2 — Calculate days inventory outstanding: 365 / 6 ≈ 61 days. On average, items sat in inventory for about 61 days before being sold.
Frequently asked questions
What is a good inventory turnover ratio for my industry?
There is no universal benchmark — a good ratio depends heavily on your industry, business model, and product type. Fast-moving consumer goods (FMCG) and grocery businesses often have ratios of 12–20 or higher because products sell quickly and margins are thin. Furniture, automotive, or luxury goods retailers typically see ratios of 2–5 because products are more expensive and sell less frequently. The best approach is to compare your ratio to industry peers and track your own trend over time. A declining ratio can be an early warning sign of excess inventory or falling demand.
Why is Cost of Goods Sold used instead of revenue in the inventory turnover formula?
COGS is used because inventory on the balance sheet is recorded at cost, not at selling price. If you divided revenue (which includes markup) by inventory at cost, the ratio would be artificially inflated and not comparable across companies with different margin structures. Using COGS keeps both the numerator and denominator on the same cost basis, giving a true picture of how efficiently inventory is being moved. Some analysts do use revenue instead — it is important to note which version you are using when making comparisons.
How can a low inventory turnover ratio hurt my business?
A low inventory turnover ratio means products are sitting in your warehouse for a long time before being sold, which ties up working capital that could be deployed elsewhere. Holding excess inventory increases storage and insurance costs, raises the risk of spoilage or obsolescence, and can signal that your purchasing or demand forecasting processes need improvement. Lenders and investors also look at inventory turnover when assessing a company's operational health — a persistently low ratio relative to peers may raise concerns about management efficiency. Improving turnover often involves better demand forecasting, tighter supplier lead times, or markdown strategies to clear slow-moving stock.