Inventory Management

If you have ever restocked a shelf back up to the same fill line every week without really thinking about it, you have used a par level. Par level inventory is one of the simplest and most practical ways to decide how much stock to hold: you set a target quantity for each item, and every time you reorder, you top up to that number. It started in bars, restaurants and hospital supply rooms, where someone walks the shelves and refills whatever has run down, and it has since become a everyday tool for retailers and ecommerce sellers who want a clear, repeatable rule for replenishment. This guide explains exactly what par level inventory is, how to calculate it, how it differs from the reorder point and safety stock it often gets confused with, where it helps and where it falls short, and how to keep par levels accurate when the same stock is selling across several channels at once.

If you have ever seen a product on a shop shelf that the shop did not actually pay for until it sold, you have seen consignment inventory at work. The supplier still owns those goods. The shop is simply holding and selling them, and money only changes hands once a customer buys. It is one of the oldest arrangements in retail, and it has quietly moved online, shaping how some marketplaces, boutiques and dropship-adjacent models operate today. This guide explains exactly what consignment inventory is, who the two parties are, how the process and the accounting work, where it helps and where it bites, and how to keep the stock counts honest when consigned goods are sold across several channels at once.

If you sell across more than one channel, every order, stock count, and price update eventually traces back to one place: your item master. It is the central record that defines what each product is, how it is identified, and how it behaves across your store, your warehouse, and every marketplace you sell on. Get it right and your inventory stays in sync everywhere. Get it wrong and you end up with duplicate SKUs, overselling, and reports that nobody trusts. This guide explains what the item master is, how item master data differs from a SKU or a product master, what fields it should contain, and how to build one that keeps a growing multichannel catalogue under control.

Days Inventory Outstanding (DIO) is the single cleanest answer to one of the hardest questions in ecommerce: how long is my cash trapped in stock before it turns back into revenue? It is a finance metric, not an operations one — your accountant, your bank, and your investors all read it — but the levers that move it sit firmly inside the warehouse and the listing platform. For a multichannel seller juggling Shopee FBS, Lazada FBL, Amazon FBA and a Shopify 3PL, DIO is also the single most underused metric for spotting which channel is quietly bleeding working capital.

If you’re holding more than a few hundred SKUs, you have a focus problem. Every item demands the same checks — counts, reorders, supplier reviews, photo refreshes — but only a fraction of them actually moves the P&L. ABC analysis inventory is the simplest tool in inventory management for fixing that focus problem. You sort SKUs into three tiers based on annual revenue contribution, then apply different policies to each tier: tighter controls and frequent counts on the few high-value items, lighter touches on the long tail.

If your stock-on-hand spreadsheet says you should have 1,000 units but the warehouse count comes back at 978, the missing 22 are shrinkage. That tiny gap — usually 1–3% of revenue — is one of the quietest profit killers in ecommerce. The latest NRF National Retail Security Survey put total US retail shrinkage at US$112.1 billion in 2022, and the rate has been climbing every year since.