How to detect stockouts before they happen

A stockout doesn’t warn you in time if you look at it backwards. Most sellers find out when the listing has already paused. The good news: a stockout is predictable with two numbers you already have.

A stockout costs more than you think

• Direct lost sale (the obvious one).
• Loss of ranking: on Amazon and MercadoLibre, running out drops your rank. Recovering takes weeks.
• Wasted ad spend: your Ads keep sending traffic to a product no one can buy.

The metric that anticipates it: days of inventory

Days of inventory = Real available ÷ Daily sales velocity

If you have 120 units and sell 8/day, you have 15 days left. If your restock lead time is 30 days, you’re already in a guaranteed stockout: you should have ordered two weeks ago.

The early-warning system

1. Compute days of inventory per product, daily.
2. Set a threshold = lead time + buffer (e.g., “warn me when below 35 days”).
3. Cross-check what’s already in transit so you don’t over-alert.
4. Get the warning before, not when stock hits zero.

Why the manual approach fails

Checking stock “now and then” doesn’t scale. With dozens or hundreds of SKUs, there’s always one crossing the threshold exactly when you’re not looking. Detection must be automatic and continuous.

In short

Stockouts are anticipated with days of inventory and threshold alerts on real available. It’s the difference between restocking in time and losing rank. iqseller watches your days of inventory and warns you before the stockout.

Want alerts before you run out? Join the beta waitlist.