Inventory how-to

What to do when sales suddenly spike

Check whether the spike is real demand or a one-off event, then decide if your reorder math needs a manual override.

Short answer: Check whether the spike is real demand or a one-off event, then decide if your reorder math needs a manual override. A sudden spike can push your 28-day average up fast, but you still need to act before the forecast catches up or you will run out.

Figure out why sales jumped

Look at what changed. A promotion, a social media mention, a competitor going out of stock, or a seasonal event can all cause a spike. If the cause is temporary, the spike may drop off just as fast. If the cause is structural, like a new wholesale account or a product going viral and staying popular, treat it as a new baseline.

Do not wait for the forecast to catch up

A forecast based on a 28-day sales window will average the spike in with slower weeks before it. That means your order-by date and suggested quantity will lag behind what you actually need. During a spike, check your on-hand stock and days of cover by hand for the affected SKUs rather than trusting the automated number alone.

Talk to your supplier early

If you need more stock than usual, contact the supplier before you hit your normal order-by date. Ask about their current lead time, since a spike in your sales might mean other retailers are also ordering more, which can stretch their lead time. Confirm case pack sizes and minimums so you are not stuck ordering less than you need.

Watch for the comedown

Once the spike passes, sales will drop back toward normal. If you ordered heavily during the spike, you may end up overstocked for a few weeks. Keep an eye on days of stock after the spike so you do not reorder again too soon.

Step by step

  1. Check what caused the spike and whether it looks temporary or lasting
  2. Calculate current days of stock by hand: on hand divided by the new, higher daily sales rate
  3. Contact your supplier early if you think you will need to reorder sooner than planned
  4. Ask the supplier about their current lead time, since it can change under demand pressure
  5. Place a manual order if the automatic order-by date is too far out to protect stock
  6. After the spike ends, recheck days of stock before placing your next order
  7. Let the forecast rebuild over the following weeks as normal sales data comes in

Worked example

Suppose a product normally sells 4 units a day and you carry 60 units, giving you 15 days of stock. A mention online pushes daily sales to 20 units overnight. At that new rate, 60 units only covers 3 days, not 15. If your supplier's lead time is 10 days and your safety stock is 2 days, your reorder point should now be 20 x (10 + 2) = 240 units, far above your current stock of 60. You need to order right away rather than wait for the system's 28-day average to reflect the spike.

How SteadyShelf helps

SteadyShelf's forecast uses a 28-day sales window by default, so it will not immediately reflect a sudden spike, you may need to place a manual order and adjust quantities yourself in the short term. Once the spike has run for a while, it will feed into the rolling average and the order-by dates and suggested quantities will catch up.

$29/month flat, unlimited products and suppliers, 30-day free trial. Run the numbers now with the free reorder point calculator.

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FAQ

Will SteadyShelf automatically detect a sales spike and reorder more stock right away?

No. It uses a 28-day sales window by default, so a spike only gradually raises the average. For an immediate need, check days of stock manually and place an order yourself rather than waiting for the suggested quantity to update.

Can I tell the difference between a real demand increase and a short-term spike using SteadyShelf?

Not directly. SteadyShelf shows sales trends per variant, but deciding whether a jump is permanent or temporary is a judgment call based on what you know about the cause, such as a promotion or press mention.

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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