Calculating your GMROI is straightforward once you know the GMROI formula and what each input means. This guide explains the method in plain language, walks through a manual calculation, and gives worked examples you can follow — then you can do it instantly with the GMROI Calculator.
What is GMROI?
The GMROI calculation tells you your GMROI from a few simple inputs. The figure you are solving for here is the GMROI.
The GMROI formula
The core formula is:
GMROI = Gross margin (currency) ÷ Average inventory costHere is what each input means:
- Gross margin (currency) — a money amount. Example: ₹2,00,000.
- Average inventory cost — a money amount. Example: ₹1,00,000.
How to calculate it step by step
- Write down the gross margin (currency) (for example, ₹2,00,000).
- Write down the average inventory cost (for example, ₹1,00,000).
- Apply the formula above to get your GMROI.
- Double-check the result with the GMROI Calculator.
Worked examples
Example 1
| Input / Output | Value |
|---|---|
| Gross margin (currency) | ₹2,00,000 |
| Average inventory cost | ₹1,00,000 |
| GMROI | 2.00 |
With gross margin (currency) of ₹2,00,000 and average inventory cost of ₹1,00,000, the GMROI works out to 2.00.
Example 2
With gross margin (currency) of ₹4,00,000 and average inventory cost of ₹1,00,000, the GMROI works out to 4.00.
| Result | Value |
|---|---|
| GMROI | 4.00 |
Example 3
With gross margin (currency) of ₹1,00,000 and average inventory cost of ₹1,00,000, the GMROI works out to 1.00.
| Result | Value |
|---|---|
| GMROI | 1.00 |
Tips for an accurate result
- Keep your units consistent — mixing, say, months with years or grams with kilograms is the most common source of error.
- Round only at the very end. Rounding inputs early can shift the final answer noticeably.
- Re-run the numbers whenever an input changes, rather than estimating from an old result.
Prefer not to do the maths by hand? — the GMROI Calculator does it instantly, for free, with the formula and a worked example built in.
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