Inventory Management Basics: Keep Stock Without Overspending

Poor inventory management quietly bleeds businesses dry. Too much stock ties up cash and risks obsolescence. Too little stock means lost sales and frustrated customers. Getting it right is the difference between a thriving business and a struggling one.

Why Inventory Management Matters

• Cash flow: Every dollar sitting in unsold inventory is a dollar you cannot spend on growth
• Storage costs: Warehouse space, insurance, and handling add 20-30% annually to the cost of holding inventory
• Customer satisfaction: Stockouts drive customers to competitors, and many never come back
• Waste reduction: Perishable or trend-dependent products lose value quickly

Key Inventory Metrics

Inventory Turnover Rate

How many times you sell and replace your inventory in a given period.

Formula: Cost of Goods Sold ÷ Average Inventory Value

• High turnover (8-12x/year): You sell quickly but risk stockouts
• Low turnover (2-4x/year): You may be overstocked or carrying slow-moving products
• Industry varies: Grocery stores turn 14+ times; furniture stores may turn 4-6 times

Days Sales of Inventory (DSI)

How many days it takes to sell your current inventory.

Formula: (Average Inventory ÷ COGS) × 365

A DSI of 30 means you hold about one month of stock. For most businesses, 30-60 days is healthy.

Reorder Point

The inventory level at which you should place a new order.

Formula: (Average Daily Sales × Lead Time in Days) + Safety Stock

If you sell 10 units per day, your supplier takes 7 days to deliver, and you want 3 days of safety stock: (10 × 7) + (10 × 3) = 100 units.

Inventory Management Methods

FIFO (First In, First Out)

Sell oldest stock first. Essential for perishable goods and recommended for most businesses to prevent obsolescence.

ABC Analysis

Categorize inventory by value and volume:

• A items (20% of SKUs, 80% of value): Track closely, reorder frequently
• B items (30% of SKUs, 15% of value): Moderate attention
• C items (50% of SKUs, 5% of value): Minimal oversight, bulk order

Just-In-Time (JIT)

Order inventory only as needed. Reduces holding costs dramatically but requires reliable suppliers and accurate demand forecasting.

Common Inventory Mistakes

1. Manual tracking with spreadsheets — Errors accumulate and real-time visibility is impossible
2. Ignoring lead times — If your supplier needs 3 weeks, you cannot reorder when stock hits zero
3. No safety stock — Supply chain disruptions happen; always maintain a buffer
4. Treating all products equally — Your best-sellers deserve more attention than slow movers
5. Not conducting regular audits — Physical counts should verify your system data quarterly at minimum

Getting Started

Start simple: track what you have, what sells, and how fast. Set reorder points for your top 20 products. Review weekly. Expand from there.

Use our Inventory Tracker to monitor stock levels, set reorder alerts, and gain visibility into your inventory performance — all without complex software.