GMROI Calculator - Gross Margin Return on Inventory

Gross Margin Return on Inventory (GMROI)

GMROI tells you how many dollars of gross profit you generate for every dollar invested in inventory. It combines margin and inventory turnover into a single number, making it one of the most important KPIs for any retail or wholesale business.

Formula:

GMROI = Gross Profit / Average Inventory Cost

Equivalently:

GMROI = Gross Margin % × (Sales / Average Inventory Cost)

Where:

• Gross Profit = Revenue - Cost of Goods Sold (COGS)
• Average Inventory Cost = (Beginning Inventory + Ending Inventory) / 2
• Inventory Turnover = COGS / Average Inventory (the turnover shown in the result panel)

Note the equivalent form above divides Sales by average inventory, not COGS. The classic GMROI identity uses sales-based turnover, which is why margin × turnover only reproduces the ratio when turnover is measured at retail, not at cost.

What a good GMROI looks like:

Industry benchmarks:

• Grocery: 4–7x (low margins, very fast turnover)
• Apparel: 1.5–3.0x (moderate margins, slower turnover)
• Jewelry: 1.0–2.5x (high margins, very slow turnover)
• Electronics: 2.5–4.0x (low margins, moderate turnover)

GMROI reveals the margin-turnover trade-off:

A luxury store with 60% margins, whose inventory turns over once a year measured at retail, has a GMROI of 0.60. That is terrible: every dollar of stock earns 60 cents of gross profit a year, before a single cost of holding it. A grocery chain with 25% margins turning 8x a year at retail has a GMROI of 2.0, which is more than three times better on a third of the margin.

Both examples use turnover measured at retail, matching the margin × turnover identity above. The result panel shows you both: turnover at cost (COGS ÷ inventory, the figure most inventory reports use) and turnover at retail (sales ÷ inventory, the one that reproduces GMROI).

How to improve GMROI:

• Reduce dead stock and clearance markdowns
• Negotiate better COGS with suppliers
• Improve forecasting to reduce overbuying
• Focus on faster-turning, higher-margin categories