Your stock no longer adds up. There is something in the system that is not on the shelf, or you sell something you do not have. So you start shopping for software. The difficult part is that the market sells you four different things under roughly the same banner, and the prices are a factor of twenty apart.
Short answer: there are four levels. A spreadsheet is fine until more than one person needs to be in it, you sell through several channels, or you no longer trust your own numbers. A standalone stock package suits anyone who only needs to sort out inventory and has nothing else to connect. A WMS is for a warehouse problem rather than a stock problem: it is about where something sits and how you pick it efficiently. And the inventory module in your ERP is usually the right answer as soon as stock is connected to sales, purchasing and accounting. Most companies are shopping one level higher than they need.
The four levels, and where you outgrow each
Level 1: the spreadsheet. Do not underestimate it. For a business with a few hundred items, one location and one person keeping stock, a spreadsheet is fast, free and understood by everyone. You outgrow it at three moments: when a second person needs to be in it at the same time, when you sell through more than one channel, or when you start counting more often than you reorder. That last one is the sharpest signal, because counting is what you do when you no longer believe your own records.
Level 2: a standalone stock package. Barcode scanning, reorder points, multiple locations, an app on the floor. A perfectly good category, and for a business without other systems often exactly enough. The problem only appears when something else arrives beside it: a webshop, an accounting package, a sales system. Every integration then becomes a place where the truth can drift apart.
Level 3: a WMS. This is where most of the confusion sits, and therefore most of the wasted money. A warehouse management system does not solve a stock problem but a warehouse problem: where do I put this down, in what order does the picker walk, how do I stop two people heading for the same rack. If your warehouse is a room, you do not need this. If your warehouse is a hall where picking routes genuinely matter, you do. We work that distinction out separately in warehouse management software.
Level 4: your ERP inventory module. As soon as stock is connected to sales, purchasing, manufacturing and accounting, a separate inventory solution is usually the more expensive route. Not because of the licence, but because of the integration you buy with it and keep maintaining.
The distinction that decides most choices
If you take one thing from this page: inventory management answers how many, a WMS answers where and how.
Do you have too much or too little of things, reorder too late, or find your valuation is off? That is inventory. Are your people walking too far, does it take too long for an order to leave, do people put things down in arbitrary places? That is a warehouse problem.
The two feel identical, because both surface as “our stock does not add up”. But the solutions are a factor of ten apart in cost, so it pays to establish which of the two you actually have before you go shopping.
The spreadsheet moment
Plenty of businesses search for stock control in Excel because they want to rescue their spreadsheet rather than replace it. That is a reasonable reflex, and sometimes the right answer.
What does work: formulas for reorder points, a second tab for movements, and a fixed counting day. What does not work, and what people attempt anyway: several people at once, a real-time link to a webshop, and serial number or best-before registration. Those are precisely the three things a spreadsheet was structurally never built for, and where the time you invest does not come back.
The broader step from spreadsheet to system is covered in from Excel to Odoo.
When your ERP is already enough
If you already run an ERP, the honest question is not which stock package to buy but whether you are using the module you already have. Odoo includes inventory as standard: multiple warehouses and locations, reorder points per product per location, barcode scanning, putaway and removal strategies such as FIFO and FEFO, and lot and best-before tracing. For most trading and manufacturing businesses that is more than enough.
The real advantage is not the feature list but the data model: a sales order lowers your available stock immediately, a purchase order raises it, and your accounting follows without anything being retyped. A standalone package can have the same features and still work out worse, simply because there is an integration in between.
For wholesale and distribution we take this further on the wholesale page.
When a standalone package beats us
This belongs here, because otherwise this piece is a sales pitch.
If you only have a stock question and no other systems that need to hang around it, a light, inexpensive inventory package is live faster and cheaper than an ERP project. If your warehouse logic genuinely sits at the top end, with wave picking, zone control or complex cross-docking, a specialised WMS alongside your ERP is the better answer and we will say so. And if you are still at the very beginning with a handful of items, the honest message is that your spreadsheet is fine and your money is better spent elsewhere.
Unsure whether you have a stock problem or a warehouse problem? Book a free Quickscan and we will walk through your items, locations and order flow before anything gets purchased.
Read more: Warehouse management software: can Odoo handle your warehouse? · From Excel to Odoo · Odoo for wholesale and distribution · Odoo as a PIM