How long will my supplements last?
Enter how many are in the pack and how many you take a day. The calculator gives the days it lasts, the date it runs out and the day to reorder by.
Calculator
90 days
Enter the pack and the amount a day.
How it is worked out
The days a pack lasts are how many are in it divided by how many you take a day, rounded down to whole days: a 180-tablet pot at 2 a day lasts 180 ÷ 2 = 90 days. It runs out on the first day without a full day’s amount left. Taken on weekdays only, each week uses five days’ worth; every other day, half as much, so the same pot lasts longer in weeks.
The day to reorder by allows 3 working days for delivery and 2 spare days, asMy stack does when a retailer’s own delivery time is not known. My stack keeps these dates for everything you take, and moves them when you log an order or correct the count.
How long a pot lasts
| In the pot | 1 a day | 2 a day | 3 a day |
|---|---|---|---|
| 30 | 30 days | 15 days | 10 days |
| 60 | 60 days | 30 days | 20 days |
| 90 | 90 days | 45 days | 30 days |
| 120 | 120 days | 60 days | 40 days |
| 180 | 180 days | 90 days | 60 days |
| 365 | 365 days | 182 days | 121 days |
Tubs of powder
| Tub | 5 g a day | 10 g a day | 30 g a day |
|---|---|---|---|
| 250 g | 50 days | 25 days | 8 days |
| 500 g | 100 days | 50 days | 16 days |
| 1 kg | 200 days | 100 days | 33 days |
Arithmetic only: these are not amounts to take. A label’s serving says what one serving is.
Questions
How do I work out how long a bottle of tablets lasts?
Divide the number of tablets in the bottle by how many you take a day. 60 tablets at 1 a day last 60 days; at 2 a day, 30 days.
What about a tub of powder?
Use grams: the tub’s weight divided by the grams you take a day. A label may give a serving as scoops; it also says how many grams a scoop holds.
When should I reorder?
Before the last few days’ worth, allowing for delivery. The retailers we compare state between 1 and 5 working days for standard delivery; My stack uses each retailer’s own stated time.
More calculators
- Supplement cost per dayA pack’s cost a day, month and year at your amount, and which of two packs is cheaper.
- IU to µg (mcg) converterVitamin D, A and E between IU and micrograms or milligrams.
- My stackEverything you take in one place: run-out dates, the day to reorder by and the cost a day.