Inventory Turnover Ratio: Calculate and Benchmark Yours

Inventory sitting on your shelves is cash you can’t use. The inventory turnover ratio tells you how efficiently you’re converting stock into sales — and whether you’re holding too much, too little, or just right. It’s one of the most useful numbers a small business owner can track, and it takes about five minutes to calculate.

What Inventory Turnover Actually Means

Inventory turnover measures how many times you sell through your entire inventory in a given period. A turnover ratio of 6 means you’ve sold through your average inventory six times in a year — roughly every two months. A ratio of 2 means you’re holding inventory for six months before selling it.

Higher turnover generally means your cash isn’t locked up in product. Lower turnover means capital is sitting in your warehouse or stockroom instead of working for you.

The formula has two versions:

Using Cost of Goods Sold (more accurate): Inventory Turnover = COGS ÷ Average Inventory Value

Using Revenue (easier if you don’t track COGS separately): Inventory Turnover = Revenue ÷ Average Inventory Value

Average Inventory = (Beginning Inventory + Ending Inventory) ÷ 2

Setting It Up in Google Sheets

Create a simple table with annual or quarterly data:

Period	Beginning Inventory ($)	Ending Inventory ($)	Average Inventory	COGS	Turnover Ratio	Days in Inventory
Q1 2025			=(B2+C2)/2		=E2/D2	=365/F2
Q2 2025

Days in Inventory converts the ratio into a more intuitive number: how many days, on average, a product sits in your inventory before being sold. Turnover of 6 = ~61 days in inventory. Turnover of 12 = ~30 days. This is easier to reason about for most business owners.

For monthly tracking, use =30/TurnoverRatio instead of 365.

What’s a Healthy Number?

There’s no universal answer — it varies enormously by industry. Here are general benchmarks:

Industry	Typical Turnover Range
Grocery / Food	20-30+
Convenience / Pharmacy	10-15
Apparel / Clothing	4-6
Hardware / Tools	5-8
Furniture	3-5
Electronics	8-12
Industrial/B2B Parts	4-8
Specialty / Niche Retail	2-4

The most useful comparison isn’t industry averages — it’s your own trend over time. If your turnover was 6 last year and it’s 4 this year, something changed. Either you’re holding more inventory, your sales slowed, or both. That’s worth investigating.

Interpreting High Turnover

High turnover sounds like a win, and usually it is. But turnover that’s too high can signal problems:

• Stockouts: You’re selling through so fast you can’t keep up. Customers who want to buy can’t. Calculate your stockout rate alongside turnover — if you’re losing sales to empty shelves, turnover may be high for the wrong reason.

• Understocking: You might be ordering too conservatively, forcing frequent small orders that cost more in shipping and processing than holding a little more inventory would.

• Pricing too low: If product is flying off shelves, are you charging enough? High turnover with thin margins is less valuable than moderate turnover with healthy margins.

Interpreting Low Turnover

Low turnover usually means one of these things:

You’re over-buying. You ordered too much relative to demand. The fix is tighter purchasing discipline and reorder point tracking (see the reorder point guide).

Products are sitting unsold. Some SKUs are dragging your overall turnover down. Use an SKU-level turnover analysis to find the dead weight.

Pricing is too high. If product isn’t moving, the market may be telling you the price is wrong.

Seasonality. Your year-end snapshot might catch you at peak inventory but before peak sales. Quarterly tracking gives a more accurate picture than annual.

SKU-Level Turnover Analysis

Overall turnover can hide problems. Build a per-SKU analysis to find your worst performers:

SKU	Annual COGS	Avg Inventory Value	Turnover	Days in Inventory	Action
Widget A	$12,000	$1,000	12	30	Keep
Widget B	$800	$2,400	0.33	1095	Discontinue or discount

Sort by Days in Inventory descending. Anything over 180 days needs a decision: discount and sell, return to supplier, donate (for a tax write-off), or write off. Dead inventory isn’t free — it takes up space, requires counting, and ties up cash.

Formula for SKU-level turnover: =SUMIF(SalesData[SKU], A2, SalesData[COGS]) / AVERAGEIF(InventoryData[SKU], A2, InventoryData[Value])

Connecting Turnover to Cash Flow

Inventory turnover directly affects cash flow. Here’s how to calculate how much cash is trapped in inventory:

Cash Tied Up = Average Inventory Value

If you could turn inventory twice as fast with the same sales volume, you’d need half the inventory investment. The difference is cash you could use for payroll, marketing, or paying down debt.

This is why turnover matters: it’s not just an efficiency metric. It’s a measure of how much working capital your inventory strategy requires.

Next Step

Pull your COGS and inventory values from your last full year. Calculate your overall turnover ratio and days in inventory. Then pull the same data broken out by your top 20 SKUs. Sort by days in inventory. Identify the bottom five performers and make a decision about each one this week.