What this calculator does
A pack lasts its total sheets divided by household daily use. Twenty-four rolls of 200 sheets is 4,800 sheets, and a household of four using six sheets five times a day gets through 120 a day, so the pack lasts 40 days.
The figure that varies most is sheets per use, and it is both the least discussed and the most consequential. Doubling it from six to twelve halves how long any pack lasts, which swamps differences in roll count or sheet count between brands.
The formula
Total sheets are the roll count multiplied by sheets per roll. Household daily use is the number of people multiplied by sheets per use and uses per day. Dividing the first by the second gives the days the pack lasts. Rolls per week works backwards from the same daily figure.
| Term | Meaning |
|---|---|
| Sheets per roll | Varies enormously between brands, from about 150 to over 400 for a double-length roll. |
| Sheets per use | The dominant variable and the least standardised. Estimates in the literature range from 5 to 15. |
| Household daily use | People multiplied by sheets per use multiplied by uses per day. |
The inputs explained
| Field | What to enter |
|---|---|
| Rolls in the pack | Number of rolls in the pack. |
| Sheets per roll | Sheets per roll, from the packaging. Compare this rather than roll count when comparing packs. |
| People in the household | Number of people in the household. |
| Sheets used, per use | Sheets per use. Around 6 to 8 is a common estimate. |
| Uses per person, per day | Uses per person per day. Five to seven is typical for an adult. |
When to use it
Working out how often to buy
Knowing a pack lasts 40 days turns restocking into a schedule rather than a surprise.
Comparing packs honestly
Packs are marketed by roll count while rolls differ hugely in sheet count. Total sheets is the figure that actually matters and the one to compare on price.
Stocking up sensibly
Calculating how long a bulk purchase lasts against the storage space it needs is the practical form of the question.
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How long does each pack size last?
A range of pack sizes for the same household.
| Rolls in the pack | Pack lasts | In weeks | Total sheets in the pack | Rolls used per week |
|---|---|---|---|---|
| 12 | 20.0 days | 2.9 weeks | 2,400 | 4.2 |
| 24 | 40.0 days | 5.7 weeks | 4,800 | 4.2 |
| 36 | 60.0 days | 8.6 weeks | 7,200 | 4.2 |
| 48 | 80.0 days | 11.4 weeks | 9,600 | 4.2 |
Questions
How many sheets does a person use?
Estimates vary widely, commonly cited between 5 and 15 sheets per use with 6 to 8 a reasonable middle. It is not a well-measured quantity and varies between individuals more than between households, which is why it is an input rather than a constant.
Should I compare roll count or sheet count?
Sheet count, and ideally total sheets per pack. Roll counts are marketing: a pack of 9 double-length rolls can hold more than 18 standard ones. Dividing the price by total sheets is the only sound comparison.
How much should I keep in stock?
Enough to cover the gap between shopping trips plus a margin. For most households two to four weeks is ample, and beyond that the storage space usually matters more than the convenience.
Does ply affect how long a roll lasts?
Indirectly. Thicker multi-ply paper means people often use fewer sheets per use, which partly offsets the fewer sheets per roll. The two effects are hard to separate, so comparing on sheets alone slightly favours thin paper.
For household running costs generally, see the shower cost calculator. For firewood, see the firewood calculator.