GMROI Calculator for Wholesale Distributors
GMROI tells you how much gross margin each dollar of inventory earns in a year. Two product lines with the same margin percent can differ sharply in GMROI if one turns four times and the other twice. This calculator shows the ratio, the turns behind it and the carrying cost.
Your numbers
Net of returns and discounts.
Average of month-end balances is better than a single snapshot.
Capital, storage, insurance, shrink and obsolescence.
Your results
GMROI is a ratio of gross margin to inventory at cost. Use it to compare product lines and branches, and pair it with service level so you do not cut stock that customers need.
GMROI as average inventory grows
Sweeps Average inventory at cost from 1200000 to 4800000, holding your other inputs fixed.
GMROI by product line from your ERP
An optional review of automating this view from inventory and sales tables.
Optional. The tool and every export work without this. No spam.
How to use the calculator
Enter annual net sales and cost of goods sold, then average inventory at cost. The result shows gross margin, GMROI, turns and days of inventory. Run it for the whole company first, then for each product line or branch by entering that group's figures. Use the carrying cost slider to see the margin left after the cost of holding inventory.
- Use average inventory, not year-end
- Use cost, not selling value, for inventory
- Compare like with like, such as one product line to another
- Revisit quarterly
The formula
GMROI equals gross margin dollars divided by average inventory at cost. It can also be written as gross margin percent multiplied by sales divided by average inventory. In the default example, gross margin is 3,000,000 and average inventory 2,400,000, so GMROI is 1.25. Turns are cost of goods divided by average inventory, 3.75 here, which is about 97 days of inventory.
Reading the result
A GMROI above 1.0 means the gross margin more than covers the inventory investment, but the real hurdle is your carrying cost rate. At 22 percent, the example carries about 528,000 a year, so the gross margin after carrying cost is still positive. Lines with GMROI below the carrying rate destroy value, they are candidates for tighter stocking or exit. Use the chart to see how adding stock reduces the ratio.
Common mistakes
Using year-end inventory when stock was seasonally low or high, mixing retail value and cost, and comparing categories with different natural turn rates. Also remember that cutting inventory improves GMROI only if sales hold. Watch fill rate alongside the ratio.
Frequently Asked Questions
What is a good GMROI for a distributor?
It varies by industry and product mix. Many distributors look for a GMROI comfortably above their carrying cost rate, and often 2.0 or higher for healthy lines. Compare your own lines and trend over time rather than relying on a single number.
Why use average inventory?
A single snapshot can be inflated or depressed by timing. Averaging month-end balances smooths seasonal swings and gives a fairer picture of the capital tied up during the year.
How is GMROI different from inventory turns?
Turns measure speed, GMROI measures profit per inventory dollar. A fast-turning, low-margin line may have the same GMROI as a slow, high-margin one. GMROI is the better guide for stocking decisions because it includes both.
What carrying cost rate should I use?
Finance usually sets it. Components include the cost of capital, storage, insurance, taxes, shrink and obsolescence. Rates between 15 and 30 percent are commonly cited, but use your own figure.
If you want GMROI by product line and branch calculated from your ERP inventory and sales data, with a human reviewing the result, we can discuss a read-only analysis.
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