Inventory Turnover Ratio Calculator

What is inventory turnover ratio — and what does it tell you?

Inventory turnover ratio measures how many times your business sold through its entire inventory over a period — usually one year. The formula is simple: divide your Cost of Goods Sold by your Average Inventory Value. A ratio of 6 means you cycled through your entire stock six times during the year. A ratio of 1.5 means you barely moved through it once.

The number matters because inventory is capital. Every dollar sitting in unsold stock is a dollar not working for you — not funding ads, not covering payroll, not available for the next product launch. High-turnover businesses run lean and efficient. Low-turnover businesses tie up cash in stock that may never sell.

The inventory turnover formula, explained

COGS is the direct cost of producing or acquiring the products you sold — not your total revenue. Average Inventory Value is typically your beginning-of-period inventory plus end-of-period inventory, divided by two. If you only have one figure handy, use it — the result is still directionally useful.

Industry benchmarks for Shopify stores

Apparel and fashion stores typically turn inventory 4–6 times per year. Electronics move faster at 6–8x because margins are thinner and product cycles are shorter. Grocery and food businesses are outliers at 12–20x because perishables force constant movement. General retail — the category most Shopify stores fall into — benchmarks between 4 and 8x.

If your ratio falls below 2, that's a signal worth taking seriously. It typically means you over-ordered on products that aren't moving, you have a pricing problem relative to demand, or your dead SKU count is dragging the overall figure down. Fixing dead inventory directly improves turnover — removing slow SKUs from your average inventory value raises the ratio without requiring more sales.

How to improve your inventory turnover on Shopify

The four most effective levers are: running markdown campaigns on slow-moving products to free up capital, tightening purchase order quantities so you hold less average inventory, concentrating paid ad spend on high-velocity SKUs rather than spreading budget thin, and cutting products that consistently underperform across multiple inventory cycles. You don't need to hit industry-average turnover overnight — a 20–30% improvement in one year is a meaningful operational win.

ShelfMerge surfaces slow-movers automatically by comparing each product's sales velocity against its current stock level. Dead inventory classifications update daily so you catch the slowdown before it becomes a write-off problem.

Turnover ratio vs. days inventory outstanding

Days inventory outstanding (DIO) — or days to sell — is just the inverse of turnover expressed in days: 365 divided by your ratio. A turnover of 4x equals 91 days to sell through inventory. Some business owners find DIO easier to reason about because it maps directly to reorder planning. If your supplier lead time is 30 days and your DIO is 25 days, you're cutting it very close.

Common questions about inventory turnover ratio