Demand Forecast

Demand Forecast predicts how many units of each SKU you will sell over the next 13 weeks, then works out how much safety stock to hold and when to reorder. It replaces guesswork with numbers you can check, and it powers the forecast-driven reorder suggestions on your Overview.

Key capabilities

• One row per SKU: model, demand pattern, a 13-week forecast curve, and weekly demand
• Safety stock, Reorder pt, and Order to (order-up-to) quantities for each SKU
• An Accuracy score for every forecast, color-coded green, amber, or red
• A detail view that overlays actual weekly sales on the forecast with a confidence band
• Recompute to refresh forecasts on demand; they also refresh nightly
• Suggested transfers on the Transfers tab to rebalance stock between locations
• Plan against cash on the Overview to test reorders against your 13-week cash curve
• Search by SKU; the tab needs the Commerce & Inventory add-on and works in any inventory mode

How it works

Forecasts are built from your Shopify order history, with refunded and voided orders left out. For each SKU, DayZero tests several forecasting methods on past weeks, keeps the one that predicted best, and uses it to project forward. The forecast then feeds safety stock, the reorder point, and the reorder suggestions.

flowchart LR
  sales["Shopify sales history"] --> forecast["13-week forecast"]
  forecast --> points["Safety stock and reorder point"]
  points --> reorders["Suggested reorders"]
  reorders --> plan["Plan against cash"]
  plan --> pos["Draft purchase orders"]

How to use it

1. Open Demand Forecast from the Insights group in the Inventory sidebar.
2. Find a SKU with the search box, or sort the table. Read Weekly (average units per week), Safety, Reorder pt, and Order to.
3. Click a row to open its detail view and compare actual sales to the forecast. Hover the chart to read any week.
4. Click Recompute after new sales history lands. A message tells you how many SKUs were forecasted.
5. On the Overview, open Suggested Reorders and click Plan against cash.
6. Tick the vendor groups to include, adjust the week cash leaves (W1 to W13), and watch the cash curve redraw.
7. Click Create draft POs for the selected vendors, then finish each draft in Purchase Orders.
8. Open Transfers to see Suggested transfers, and click the truck icon on a row to start a prefilled transfer.

Pro tips

• Without sales history there is nothing to forecast. The empty state asks you to connect Shopify and click Recompute.
• Trust the Accuracy score, not just the curve. Up to plus or minus 20% is green, up to 50% amber, and above that red. Lumpy or very new SKUs often score poorly.
• Lead time comes from the SKU's default vendor, or 14 days if it has none. Set vendor lead times to sharpen reorder points.
• In Plan against cash, a red verdict means the reorders push cash below zero. Defer lower-urgency vendors or move their cash week later.
• Items with no default vendor are left out of reorder plans, so assign vendors on Products.
• Suggested transfers use each location's reorder point, not the forecast, so keep those current in Locations & Transfers.

In-depth guide

The table

Demand patterns are Smooth (steady), Erratic (steady but swingy), Intermittent (many zero weeks), Lumpy (zero weeks and big spikes), and New (no sales recorded yet). Croston/SBA suits Intermittent and Lumpy items; Holt-Winters picks up trend and yearly seasonality when there are enough weeks.

The detail view

The chart shows up to 26 weeks of actual sales, a divider at "now", and the forecast with a shaded band showing normal variation. Six tiles sit below: Avg / wk, σ / wk, Service, Lead time, Safety, and Accuracy. A sentence then states the plan, for example holding a number of units of safety stock at a 95% service level, reordering at a set point, and ordering up to a target. If a SKU has no forecast yet, the view shows sales history only.

Plan against cash

The planner compares your 13-week cash today with cash after the selected reorders. Four tiles summarize it: Selected spend, Lowest cash (now), Lowest cash (after), and Low-point change. Each vendor row starts with cash leaving after lead time plus payment terms. If the vendor offers an early-payment discount, Pay early to save moves the payment earlier and cuts the cost, and Take all discounts applies it everywhere. Only the vendor selection carries into the draft POs. Set delivery dates and early-pay terms on each draft.

Suggested transfers

This panel lists a variant, a quantity, a donor location holding at least 25% above its own reorder point, and a receiver below its reorder point. Each location chip shows stock against reorder point. If everything is balanced, it says nothing needs rebalancing.