Reorder interval calculator for consumable products
Work out how long one pack lasts a customer and what usage days to set, so each reorder reminder arrives a few days before they run out. Use the result to decide the usage days you enter in Reorder Reminder Pro.
Use the number in Reorder Reminder Pro
Enter the usage days against the product. Every customer who buys it gets their reminder that many days after their own purchase date, with a button that goes straight to checkout.
How to choose the timing for a reorder reminder
A reorder reminder works when it arrives shortly before the customer's supply is used up: early enough for them to order and receive the next pack, late enough that they have noticed they are running low. Send it too early and it gets ignored; send it too late and they may have already bought from someone else.
1. Work out how long one order lasts
Start from the product label. Divide the amount in the pack by the amount a typical customer uses each day. A 60-capsule supplement at two a day lasts 30 days. A 1 kg bag of coffee at 36 g a day lasts about 27 days. A 12 kg bag of dog food fed at 300 g a day lasts 40 days. If customers usually buy two packs, double it.
2. Subtract a buffer
The buffer is the gap between the reminder and the day the pack is finished. It covers the time to see the email, order and wait for delivery. Three to seven days suits most stores. Lean longer when delivery is slow, or for things customers cannot go without, such as pet food. The result is the number of usage days to set.
3. Set it per product, not per store
Different products last different lengths of time, even within one brand. A 30-day tub and a 90-day bottle need different numbers, and so do different sizes of the same product. One store-wide number only works if every product genuinely lasts the same time.
4. Check against real repeat orders
The label gives you a starting point, not the truth. Some customers skip days, share a tub between two people, or take a double dose. After the first round of reminders, look at when customers actually reorder. If most reorder well after the reminder, increase the usage days; if they reorder before it, reduce them.
Common mistakes
The most common mistake is using the pack length with no buffer, so the reminder lands on the day the customer runs out, too late to order and receive the next one. The second is timing from the shipping date instead of the purchase date, or assuming every product lasts 30 days because a monthly reminder is convenient. Products that customers use unevenly, such as SPF in summer or pet food for a growing puppy, need a review after the first cycle more than steady daily supplements do.
Writing the email itself? The free reorder email generator drafts subject lines and body copy from a product URL, and the checkout URL generator builds a link that opens checkout with the product in the cart. For typical supplement figures, see supplement reorder reminders; for pet food, see pet food reorder reminders.
Common questions
How do I calculate when to send a reorder reminder?
Divide the amount in one pack by the amount a customer uses per day to get how many days the pack lasts. Then subtract a buffer of 3–7 days so the reminder arrives with time to order and deliver. A 60-capsule supplement taken twice a day lasts 30 days; with a 5-day buffer, send the reminder on day 25.
What are usage days in Reorder Reminder Pro?
Usage days are the number you set for each product: how many days after a customer's purchase their reorder reminder should send. Reorder Reminder Pro does not work this out for you; you decide it, and this calculator is one way to choose the number.
How long a buffer should I leave before the customer runs out?
Most stores use 3–7 days. Use the longer end if delivery takes several days, if the product is one customers cannot go without (pet food, daily medication-style supplements), or if customers tend to use it faster than the label suggests.
What if customers buy more than one pack?
Multiply the days by the number of packs. Two 30-day tubs last about 60 days, so the reminder should come later. Use the "packs per order" field to see the effect.
What is the best way to time reorder emails for pet food?
Work from the bag size and the daily feeding amount on the label for the pet size most of your customers have. A 12 kg bag at 300 g a day lasts 40 days; with a 7-day buffer, send the reminder on day 33. If you sell several bag sizes, set usage days for each one separately, because a 2 kg and a 12 kg bag of the same food run out at very different times.
Are the presets recommendations?
No. They are examples of common pack sizes and daily use to start from. Real use varies by product, dose and customer, so adjust the numbers to match your product label and what you see in your own repeat orders.
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