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What is weeks on hand (WoH)?

A quick, citable definition — plus the formula, an example, and how growth-stage brands use it.

In short: Weeks on hand (WoH) is current inventory divided by average weekly demand. It tells you how many weeks of sales your current stock will cover before you run out. A WoH below your target signals a coming stockout; a very high WoH signals overstock and trapped cash.

The formula

Weeks on hand = current on-hand inventory ÷ average weekly demand. If a SKU has 4,000 units on hand and sells 1,000 a week, it has 4 weeks on hand. Days on hand (DoH) is the same idea in days.

Why it matters

WoH turns a raw inventory count into a decision. Set a target (say, 6 weeks) that covers your replenishment lead time plus safety stock. When a SKU drops below target, it's time to reorder; when it climbs far above, you're carrying overstock and trapped cash. Track it per location and you catch a single FC running dry even when the network looks fine.

How SpyGlass uses it

SpyGlass computes weeks- and days-on-hand for every SKU at every fulfillment center against a forecast of demand, alerts you before any location breaches target, and turns that into a replenishment plan. See weeks-on-hand by FC →

Frequently asked questions

What is a good weeks-on-hand target?
Enough to cover your replenishment lead time plus safety stock — often 4–8 weeks for growth-stage brands, higher for long-lead or seasonal items.
What's the difference between weeks on hand and days on hand?
They measure the same thing at different resolution: weeks on hand is inventory ÷ weekly demand; days on hand is inventory ÷ daily demand.
How do you calculate weeks on hand?
Divide current on-hand inventory by average weekly demand for that SKU. Do it per location for a true coverage picture.

Keep reading

Weeks-on-hand by FC →Days-on-hand & cash →How to avoid stockouts →