Inventory glossary
What is Demand planning?
Demand planning is the process of estimating how much of each product you will sell in future periods, so you can buy stock, plan cash, and avoid running out or overbuying.
For a small Shopify store, demand planning is what turns past sales into a buying plan. Without it, owners either reorder by gut feeling or react only after a product sells out, which leads to lost sales or cash stuck in slow-moving stock.
In practice this means looking at each SKU's sales history, adjusting for trends or seasonality, and turning that into a number you can act on: how many units to order, and by when. Good demand planning feeds directly into reorder points, order quantities, and supplier timing.
Example
A candle store sold 40 units of its lavender candle last month and 45 the month before, with no major seasonal swing expected. The owner plans demand at roughly 40 to 45 units for next month. If the supplier's lead time is two weeks, that means ordering enough stock now to cover about three weeks of expected sales plus a buffer, rather than waiting until shelves are empty.
Common mistakes
- Relying only on last month's sales and ignoring seasonality or promotions that skewed the numbers.
- Treating demand planning as a one-time task instead of updating it regularly as sales patterns change.
- Planning demand in isolation from lead times, so even a good forecast arrives too late or too early.
Demand planning and SteadyShelf
SteadyShelf builds a demand plan automatically for each variant by forecasting sales and turning that into order-by dates and suggested order quantities based on each supplier's lead time.
SteadyShelf is launching on the Shopify App Store. Join early access to get the install link first.
Related terms
Demand forecasting · Reorder point · Lead time · Safety stock · Seasonality
FAQ
How is demand planning different from demand forecasting?
Demand forecasting is the number itself, the predicted sales for a period. Demand planning is the broader process of using that forecast, along with lead times and business goals, to decide what and when to buy.
Do small stores really need formal demand planning?
Yes, even a simple version helps. Looking at recent sales trends before placing each order is demand planning, and it prevents both stockouts and overstock better than guessing.
Let SteadyShelf do this math for every SKU
Order-by dates per supplier, seasonal forecasts and draft POs for your Shopify store. $29/month after a 30-day free trial.
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