Inventory Turnover Calculator
Work out how many times a year your stock sells through, and how long it sits on the shelf.
What this tool does
An inventory turnover calculator works out how many times a year your inventory sells through, using cost of goods sold and average inventory. Turnover = COGS ÷ average inventory, and days in inventory = 365 ÷ turnover. A ratio of 6 means the stock is replaced six times a year, sitting an average of 61 days. Higher is usually better, but too high can mean stockouts and lost sales.
Calculates inventory turnover from cost of goods sold and average inventory.
Shows days sales in inventory, which is turnover expressed as a holding period.
Suggests a restock cadence from the turnover figure.
Compares the result against typical ranges for different industries.
How to use it
- Choose a currency symbol if you want one.
- Enter cost of goods sold for the period, usually a year.
- Enter average inventory at cost - the average of opening and closing stock.
- Enter the number of days in the period if it is not a full year.
- Read the turnover ratio, days in inventory and restock cadence.
Why use this calculator
Calculating inventory turnover from cost of goods sold and average inventory puts a number on the cash sitting on your shelves. Every day of inventory is money you have paid for and not yet recovered, and the difference between 4 turns and 8 turns on the same revenue is often the difference between a business that funds its own growth and one that borrows to do it. The ratio also flags the opposite problem: a very high turnover with thin stock can mean empty shelves and lost orders.
Why we built it
We built the inventory turnover calculator to show days in inventory next to the ratio, because days is what connects the metric to cash flow - it tells you how long a stack of stock is tied up before it turns back into money. The discount and profit calculator works the margin side of the same stock, and the profit margin calculator shows what each sale contributes once it happens. For the cash cycle itself, the loan payoff calculator and the break-even calculator show what the funding costs.
If the stock is priced dynamically, the markup calculator sets the prices that the turnover then measures.
Who this tool is for
- Retailers and wholesalers reviewing stock performance
- Cafe, restaurant and grocery operators with perishable stock
- Warehouse and operations managers setting reorder points
- Owners comparing a business against industry benchmarks
When to use it
- At month or quarter end, to track the trend.
- Before renegotiating supplier terms or credit lines.
- When deciding whether to range a new product line.
- If cash is tight and stock seems to be absorbing it.
How it is calculated
Turnover = cost of goods sold ÷ average inventory. Average inventory = (opening stock + closing stock) ÷ 2, both at cost, not at retail price. Days in inventory = 365 ÷ turnover. Restock cadence in days is roughly the days in inventory if you hold exactly what you sell through a cycle. Multiply turnover by gross margin percentage to get gross margin return on inventory (GMROI), which shows profit per unit of stock invested.
Worked example: a shop with 480,000 in annual COGS and average stock of 80,000 turns 6 times a year - 365 ÷ 6 = 61 days of stock. At a 35% gross margin, GMROI = 6 × 0.35 = 2.10, meaning 2.10 of gross profit for every 1.00 sitting in stock.
Use cost, not retail price, in both figures. Mixing a retail-value inventory with a cost-based COGS inflates the ratio and hides how much cash is actually tied up. Most accounting systems report stock at cost already.
Typical turnover by industry
| Business type | Turns per year | Days in stock |
|---|---|---|
| Grocery and fresh food | 12 - 24 | 15 - 30 |
| Clothing and fashion | 3 - 6 | 60 - 120 |
| General retail | 4 - 8 | 45 - 90 |
| Furniture and appliances | 2 - 4 | 90 - 180 |
| Hardware and building supply | 3 - 6 | 60 - 120 |
| Electronics | 5 - 10 | 36 - 73 |
| Automotive parts | 3 - 6 | 60 - 120 |
Ranges are broad because they depend on seasonality, product mix and how businesses count consignment or work-in-progress stock. Trend matters more than the absolute number: a declining turnover on the same revenue means stock is piling up.
A worked example
These are the values the calculator opens with, so you can see exactly what it does with them. Change any value on the page and the result updates; the figures below come from the same calculation.
| Input | Value |
|---|---|
| Currency symbol | $ (dollar) |
| Cost of goods sold | $480,000 |
| Average inventory | $80,000 |
| Days in period | 365 |
| Gross margin | 35% |
With those inputs, the calculator returns:
- Turnover ratio: 6.0 times per year
- Days in inventory: 60.8 days
- Restock cadence: about every 61 days for a full cycle
- GMROI: 2.10
- Stock held per turn: $80,000
Reading the result honestly
Turnover alone does not say whether you are doing well. Compare it with your own history first, then with the industry range, and check it alongside margin: high turnover at 10% margin can produce less cash than low turnover at 50%. Promotions often raise turnover while lowering margin, so the two must be read together.
| Pattern | Likely meaning |
|---|---|
| Turnover falling, revenue flat | Stock accumulating - over-ordering or slowing lines. |
| Turnover rising, margin falling | Discounting to move stock; check profit per turn. |
| Turnover far above industry | Possible stockouts; lost sales on top-selling lines. |
| Turnover low, margin high | Capital tied up; may be right for luxury or bespoke lines. |
| One line drags the average | Discontinue or markdown the slow movers. |
What you enter, and what you get back
| Item | Details |
|---|---|
| COGS | Cost of the goods sold over the period, at cost. |
| Average inventory | Average stock at cost for the same period. |
| Days in period | 365 for a year, 90 for a quarter. |
| Gross margin | Optional, for the GMROI figure. |
| Result | Turnover ratio, days in inventory, restock cadence and GMROI. |
Issues you may run into
| What you see | Why it happens | What to do |
|---|---|---|
| Ratio looks implausibly high | Inventory valued at retail instead of cost. | Restate stock at cost to match the COGS basis. |
| Seasonal business skews the answer | Average of two dates misses the peak. | Average monthly stock across the year instead. |
| Turnover good but cash still tight | Supplier terms are short or margins thin. | Check payables days and gross margin together. |
| Very low turnover | Over-ordering, slow lines or obsolescence. | Markdown or discontinue; reorder less frequently. |
Assumptions and limitations
- Uses a simple two-point average; seasonal businesses should average monthly figures.
- Assumes COGS and inventory are on the same cost basis.
- Does not account for consignment, work-in-progress or obsolete stock write-offs.
- Industry ranges vary by region, product mix and accounting practice.
Frequently asked questions
How do I calculate inventory turnover?
Divide cost of goods sold by average inventory. Average inventory is (opening + closing) ÷ 2, both at cost. If COGS is 480,000 and average stock is 80,000, turnover is 480,000 ÷ 80,000 = 6 times a year. Always use cost, not retail value.
What is a good inventory turnover ratio?
It depends on the industry: 12 to 24 turns a year for grocery, 4 to 8 for general retail, and 2 to 4 for furniture. What matters most is the trend against your own history and the days-in-inventory figure that matches your supply lead time. Above the industry range can mean stockouts rather than efficiency.
What is days inventory outstanding?
The average number of days stock sits before it sells, also called days sales in inventory: 365 ÷ turnover. A turnover of 6 gives 365 ÷ 6 = about 61 days. It converts the ratio into something operational - how long your cash is tied up in goods on the shelf rather than moving through the business.
How does inventory turnover affect cash flow?
Inventory is cash you have already paid out and not yet recovered, so every day of stock is working capital held on a shelf. Higher turnover returns that cash sooner, funding payroll, new stock and growth without borrowing - which is why a business can be profitable on paper and still short of cash. Very high turnover can also mean thin stock and stockouts, so read it with margin and availability.
How can I improve my inventory turnover?
Reduce what you hold rather than only chasing more sales: discontinue slow lines, order in smaller quantities more often, tighten reorder points to lead times, and clear aged stock with markdowns before it becomes obsolete. Raising prices on in-demand lines also lifts COGS-relative turnover if volume holds.
What is the difference between inventory turnover and sell-through?
Inventory turnover measures how many times the whole stock turns over a period, using cost of goods sold against average inventory. Sell-through measures how much of a specific batch or season's stock sold within a period, as a percentage of what was received. Sell-through is per line or season; turnover is the whole business.