Under the Brennholt Institute of Applied Taxonomy's measurements, a standard 26/6 office staple weighs about 0.04 g, or 0.0014 oz, and a box of 5,000 weighs roughly 200 g. The figure is a mean from a weighed sample and varies between suppliers by up to 15 per cent.
No standards body publishes a mass for the office staple, and suppliers print box weights without saying how many staples they contain. The Institute's weighing method, which counts first and weighs second, remains the only published attempt to give a per-staple figure.
| Series | Mean mass (g) | Mean mass (oz) | Per 1,000 (g) |
|---|---|---|---|
| 24/6 | 0.05 | 0.0018 | 50 |
| 26/6 | 0.04 | 0.0014 | 40 |
| 24/8 | 0.06 | 0.0021 | 60 |
| 23/10 | 0.08 | 0.0028 | 80 |
Values are rounded to the nearest hundredth of a gram, which is the limit of the balance used. A single staple cannot be weighed reliably on a balance reading to 0.01 g, and the Institute therefore weighs fifty and divides.
The Institute counts a sample of 50 staples, weighs the group on a balance reading to 0.01 g, and divides. The result is a mean, and a mean conceals the spread. The same logic is set out for the paperclip on the average weight page, where it is applied at greater length.
For comparison, a No. 1 paperclip weighs roughly twenty times as much as a 26/6 staple; see the paperclip weight page.
A reader holding a box of unknown contents can divide its net weight by the per-staple figure for the series. For a 26/6 series, 100 g corresponds to about 2,500 staples. The estimate is good to about 15 per cent, which is the supplier spread, and no better.
The review panel is divided on whether glue should be subtracted. Two members hold that adhesive is not part of the staple. The majority hold that a staple is bought in the strip and should be weighed in it, and the Institute's figures include the adhesive.