Business

ABC Inventory Analyzer

Paste your SKUs and annual revenue. Get instant Pareto-style classification: A (top 80%), B (next 15%), C (bottom 5%).

Quick Answer

Sort SKUs by revenue descending. Top 80% cumulative = A class. Next 15% = B. Bottom 5% = C. Focus inventory effort on A items.

Paste SKU Data

Format: SKU, Revenue (one per line). Comma or tab separated.

Class A
4 SKUs
$123,000
Class B
4 SKUs
$33,500
Class C
4 SKUs
$8,400
SKURevenue% of TotalCumulativeClass
SKU-001$45,00027.3%27.3%A
SKU-002$38,00023.0%50.3%A
SKU-003$22,00013.3%63.7%A
SKU-004$18,00010.9%74.6%A
SKU-005$12,0007.3%81.9%B
SKU-006$9,0005.5%87.3%B
SKU-007$7,5004.5%91.9%B
SKU-008$5,0003.0%94.9%B
SKU-009$3,5002.1%97.0%C
SKU-010$2,2001.3%98.4%C
SKU-011$1,8001.1%99.5%C
SKU-012$9000.5%100.0%C

Total revenue: $164,900 across 12 SKUs

About This Tool

The ABC Inventory Analyzer applies the Pareto principle (80/20 rule) to SKU portfolios. Most ecommerce stores find that 20% of their SKUs drive 80% of revenue — and the bottom 50% of SKUs drive less than 5%. ABC classification is the foundation of every modern inventory management system because it tells you where to focus effort, capital, and supplier attention.

Why ABC Matters More Than Ever in Ecommerce

With Shopify and Amazon making it easy to launch SKUs, most stores accumulate hundreds or thousands of products without managing the long tail. The bottom 50% of SKUs typically tie up working capital, occupy warehouse space, and add fulfillment complexity for almost no revenue contribution. ABC analysis surfaces these underperformers and frees you to either kill them, raise prices to reset margin, or move them to drop-ship/print-on-demand to eliminate inventory carrying cost.

Managing Class A Items

A items are your business. They warrant tight tracking — weekly cycle counts, conservative reorder points with extra safety stock, multiple supplier relationships for critical SKUs. Run forecast accuracy reports on every A item monthly. Negotiate volume contracts with primary suppliers and identify backup suppliers for the top 5-10 SKUs. Stockout on an A item is materially worse than stockout on a C item.

Managing Class C Items

C items are the long tail. They generate small revenue individually but consume disproportionate operational overhead — purchase orders, shelf space, cycle counts, fulfillment touches. Many businesses simplify C items aggressively: standardize order quantities (90 days at a time), accept higher stockout risk, consolidate to one or two suppliers, or move to drop-ship arrangements. Some kill the bottom 10-20% of C items entirely each year as part of SKU rationalization.

Beyond Revenue: Multi-Criteria ABC

Pure revenue ABC sometimes misses operational risk. A low-revenue but mission-critical replacement part for an installed base might warrant A-level attention despite its small revenue contribution. Multi-criteria ABC weights revenue, margin, lead time, criticality, and supplier risk. Most small businesses do not need this complexity — pure revenue ABC plus exception flagging for critical items is sufficient.

Related Tools

See also our safety stock calculator, reorder point calculator, days of inventory calculator, AOV calculator, and dropshipping margin calculator.

Frequently Asked Questions

What is ABC inventory analysis?
ABC analysis classifies inventory by revenue contribution using the Pareto principle. Class A items typically represent 20% of SKUs but 80% of revenue. Class B items are the next 15% of revenue. Class C items are the remaining 5%, representing the bulk of SKU count but minimal revenue. The classification helps focus inventory management effort where it matters most — A items get tight tracking, conservative reorder points, and frequent counts. C items can use simpler rules.
What thresholds should I use for ABC classification?
The standard 80/15/5 split (A=top 80% of revenue, B=next 15%, C=bottom 5%) works for most businesses. Some use 70/20/10 or 80/10/10 depending on SKU portfolio breadth. The exact percentages matter less than the principle: focus disproportionate effort on the SKUs that drive disproportionate revenue. Recalculate quarterly or after major product line changes.
How should I manage A, B, and C items differently?
A items: tight cycle counts (weekly), conservative reorder points, premium safety stock, single-vendor critical items get backup suppliers. B items: standard inventory rules, monthly counts, normal safety stock. C items: simpler rules (order 90 days at a time), quarterly counts, accept higher stockout risk. Some businesses even drop C items entirely and let customers wait for special orders.
Should I classify by units sold or revenue?
Revenue is the standard for ABC analysis. A high-margin slow-mover often outperforms a high-volume low-margin item in revenue terms. Some businesses run two ABC analyses — one by revenue and one by units — to capture both economic importance and operational complexity. SKUs that score high in both deserve the most attention.
Can I use ABC analysis for purchasing too?
Yes. ABC classification informs supplier negotiation effort, contract terms, and procurement frequency. A items often justify dedicated buyer attention, longer-term contracts with volume rebates, and multi-source supply chains for resilience. C items can be consolidated to fewer suppliers or moved to consignment/dropship arrangements to reduce working capital.