What Is ABC Inventory Analysis?
ABC inventory analysis groups products by business impact so you can focus operational attention where it matters most. A-items usually produce the majority of revenue or profit, B-items are moderate contributors, and C-items make up the long tail.
For Shopify merchants, ABC analysis helps with purchasing, stock control, markdown planning, fulfillment priority, and cash flow management.
ABC Inventory Categories
The classic model follows the 80/20 principle, but the exact thresholds can vary by store.
| Class | Typical Share of Revenue | Typical Share of SKUs | Priority |
|---|---|---|---|
| A items | 70-80% | 10-20% | Protect availability |
| B items | 15-25% | 20-30% | Monitor and optimize |
| C items | 5-10% | 50-70% | Reduce, bundle, or clear |
The goal is not just classification. The goal is better decisions about reorder frequency, safety stock, buying depth, and markdown strategy.
How to Use This Tool
- Enter total SKUs and revenue.
- Add gross margin and inventory value assumptions.
- Review how revenue and profit concentrate across A, B, and C items.
- Check holding cost and GMROI by class.
- Use the C-item scenario to estimate cash freed by reducing slow-moving inventory.
ABC Analysis Formula
At its simplest, ABC analysis ranks products by contribution:
Revenue Contribution = Product Revenue / Total Revenue
You can also use profit contribution when margins vary widely:
Profit Contribution = Product Gross Profit / Total Gross Profit
For inventory-heavy stores, GMROI adds another layer:
GMROI = Gross Margin Dollars / Average Inventory Cost
How to Act on Each Inventory Class
A Items
Keep A-items in stock, forecast them carefully, and review supplier lead times. A stockout on these products has a disproportionate revenue impact.
B Items
Monitor B-items for movement into A or C status. These products often benefit from better merchandising, bundles, or reorder adjustments.
C Items
Reduce purchasing depth, bundle slow movers, run targeted markdowns, or discontinue products that tie up cash without contributing profit.
Frequently Asked Questions
How often should I run ABC analysis?
Run it monthly for fast-moving stores and quarterly for slower catalogs. Seasonal businesses should compare the same season year over year.
Should ABC analysis use revenue or profit?
Revenue is a good starting point, but profit contribution is often better when margins vary. Use GMROI when inventory investment is a major constraint.
What should I do with C inventory?
Do not automatically delete every C item. Some support bundles, SEO, or merchandising. But persistent low-profit C items should be reduced, cleared, or discontinued.
Can ABC analysis prevent stockouts?
It helps prioritize which products need tighter replenishment controls. A-items should usually have stronger safety stock and more frequent review.
About This Tool
This ABC inventory tool was built for Shopify merchants who need a fast way to understand catalog concentration, holding costs, and long-tail inventory risk.