How StockDigest works out days left and reorder amounts
StockDigest works out days left and reorder amounts with plain arithmetic, shown here step by step with a worked example you can check.
Every figure comes from three things: how fast a product sells, how much you have, and how long your supplier takes. The forecast is arithmetic, not AI. AI only writes the short highlights at the top of the email.
Sales per day
Sales per day is half the 28-day average plus half the 7-day average. The blend lets recent changes show up quickly, without one odd day swinging the result.
Both averages count whole days up to yesterday, in your store’s time zone, so a half-finished today doesn’t drag them down. Cancelled and test orders don’t count, and neither do refunded units.
Days left
Days left is stock ÷ sales per day, rounded down. Stock is what’s available to sell, added up across all your locations. A product with no sales in the last 28 days has no days-left figure, and the Dashboard shows a dash.
Status
Each product gets the first status that fits:
| Status | When |
|---|---|
| Out of stock | Nothing available |
| Runs out before restock | Days left is at or below the product’s lead time |
| Low | Days left is at most the lead time plus 7 days, or stock is at or below the low-stock level |
Products that fit none of these aren’t listed.
Reorder amount
Reorder = sales per day × (lead time + cover days) − in stock − on the way
The result is rounded up and never goes below 0. It’s enough to last until a new order arrives (the lead time), then for your cover days (the Reorder enough for setting), minus what you have and what’s already on the way.
The Dashboard’s Reorder column shows it for every listed product. In the email, it appears on products that run out before restock.
A worked example
Ceramic Pour-Over · Speckled sold 28 units in the last 28 days and 11 in the last 7. There are 12 in stock and nothing on the way. The lead time is 14 days and Reorder enough for is 30 days.
Sales per day. 28 ÷ 28 = 1.00 a day. 11 ÷ 7 = 1.57 a day. Half of each: 0.50 + 0.79 = 1.29 a day.
Days left. 12 ÷ 1.29 = 9.3, rounded down to 9 days.
Status. 9 days is less than the 14-day lead time, so the product runs out before restock.
Reorder. 1.2857 (the unrounded speed) × (14 + 30) = 56.6. Minus 12 in stock and 0 on the way leaves 44.6, rounded up to 45.
On the Dashboard, the product shows 1.3 under Sells per day (one decimal place), 9 under Days left and 45 under Reorder. In the email it’s under Needs action: “12 left”, with “about 9 days, reorder 45” underneath.
Try your own numbers in the reorder calculator, or read how much to reorder for the thinking behind each input.
Which products are included
StockDigest looks at every variant that tracks inventory, is active and isn’t a gift card, and that sold in the last 28 days or is at or below its low-stock level. Draft and archived products are left out. Each variant has its own forecast, shown as “Product · Variant”.
On Pro, stores with 2 or more locations also get stock per location.
Good to know
- Sales are refreshed each morning before the digest, which picks up recent refunds and cancellations. Refresh sales on the Dashboard does the same at any time. Stock levels on the Dashboard are always live.
- Days a product spent out of stock count as days with no sales, so its speed can read low for up to 28 days after a stockout.
- The forecast follows recent sales. It doesn’t adjust for seasons, so keep an eye on products you expect to pick up.
The settings behind these numbers are explained in lead time, cover days and the low-stock level. For an overview, see the inventory forecast.