How do you calculate inventory turns?

Divide annual COGS by average inventory. With $1.8M COGS and average inventory of $300,000 (the mean of $320k and $280k), turns equal 6 per year.

What is a good inventory turnover for manufacturing?

It varies by sector, but 4-6 turns is common for discrete manufacturers and 8+ for lean or high-velocity operations. The example's 6 turns is solid for most plants.

What does 6 inventory turns mean in days?

It means about 60.8 days of inventory on hand — roughly two months of cost of goods sitting in the warehouse before it is consumed and replaced.

Is higher inventory turnover always better?

Not always. Very high turns can mean too little buffer, risking stockouts and expedite costs. The goal is the lowest inventory that reliably feeds production.

What is the difference between inventory turns and days inventory?

They are inverses. Turns count replacements per year; days inventory (365 divided by turns) is how long stock sits. Six turns equals 60.8 days.

Should I use COGS or sales for inventory turns?

Use COGS. Sales include margin, which inflates turns and distorts the comparison. The formula here correctly uses cost of goods sold.

Planning calculator

Inventory Turns Calculator

Inventory turns measure how many times a manufacturer sells and replaces its stock in a year, and it is one of the clearest signals of working-capital efficiency on a shop floor. Operations and supply-chain planners watch it because every turn of inventory is cash freed from the warehouse and put back into the business. A plant turning stock six times a year holds roughly two months of cost of goods on the shelf — capital that could fund tooling, capacity or a buffer against demand swings. It is the metric finance and lean teams use together to decide whether to tighten reorder points, shrink safety stock or renegotiate supplier lead times.

What this calculator does

Calculate inventory turnover and days inventory on hand from COGS and average inventory.
Use when working capital and stock levels need a simple metric.
It computes annual inventory turns by dividing COGS by the average of beginning and ending inventory, and converts that to days of inventory on hand.

Formula used

Average inventory = (beginning + ending inventory) ÷ 2
Inventory turns = COGS ÷ average inventory
Days inventory = days in period ÷ turns

Inputs explained

Annual cost of goods sold: undefined
Beginning inventory: undefined
Ending inventory: undefined
Days in period: undefined

How to use the result

Use it monthly or quarterly to gauge how lean your stock is and to set targets for reducing on-hand inventory without starving the line.
A two-point average of beginning and ending inventory can mask seasonal swings; for spiky demand use a monthly average instead of just two snapshots.

Current U.S. benchmarks

U.S. manufacturing runs at 75.6% of capacity (Federal Reserve, May 2026). New factory orders are up 2.3% year over year (Census).

Common questions

How do you calculate inventory turns? Divide annual COGS by average inventory. With $1.8M COGS and average inventory of $300,000 (the mean of $320k and $280k), turns equal 6 per year.
What is a good inventory turnover for manufacturing? It varies by sector, but 4-6 turns is common for discrete manufacturers and 8+ for lean or high-velocity operations. The example's 6 turns is solid for most plants.
What does 6 inventory turns mean in days? It means about 60.8 days of inventory on hand — roughly two months of cost of goods sitting in the warehouse before it is consumed and replaced.
Is higher inventory turnover always better? Not always. Very high turns can mean too little buffer, risking stockouts and expedite costs. The goal is the lowest inventory that reliably feeds production.
What is the difference between inventory turns and days inventory? They are inverses. Turns count replacements per year; days inventory (365 divided by turns) is how long stock sits. Six turns equals 60.8 days.

Last reviewed 2026-05-12.