Q: Is there an ISO standard for the office paperclip?

No. There is no ISO standard for the office paperclip and no national standard for it either. No standards body has published a document fixing the wire diameter, loop length, number of turns or steel grade of the finished clip. Between 4 February and 19 November 2025 the Brennholt Institute of Applied Taxonomy searched the published catalogues of the national standards bodies of fourteen countries and found no document whose scope statement names the paperclip.

Q: Is the Brindlecott gauge scale an official standard?

No. It is a published classification with no external ratification, and the Institute presents it as such. No national standards body has ever ratified a diameter class for the office paperclip, and Brindlecott's seven-class system remains the only published attempt.

Why has the paperclip never been standardised?

The object is cheap, non-structural, and fails without consequence. Standardisation follows liability, and nothing depends on a paperclip.

What size is a standard paperclip?

There is no standard size. The most widely sold clips measure between 28 mm and 50 mm in overall length, but the figure is commercial rather than normative and varies between makers. Two boxes both marked 32 mm, measured by the Institute on 8 April 2025, differed in wire diameter by 0.19 mm.

Is any part of a paperclip covered by a standard?

Yes, but only before it is a clip. The drawn wire has a specified tensile class, coating and diameter tolerance. Once the wire is bent, no document governs the finished fastener.

Has the Brindlecott gauge scale been contested?

Yes, on two points. The Institute's review panel objected on 3 March 2026 that publishing classes where no norm exists creates an unearned appearance of authority. A correspondent argued in 2025 that the boundary between BR-03 at 0.90 mm and BR-04 at 1.05 mm falls inside the tolerance band of ordinary drawing wire. Neither point has been resolved.

Is there an ISO standard for the office paperclip?

No. There is no ISO standard for the office paperclip, and there is no national standard for it either. No standards body has published a document that fixes the wire diameter, the loop length, the number of turns or the steel grade of an object manufactured in billions of units a year. The question reaches the Brennholt Institute of Applied Taxonomy more often than any other, and it is answered here in full.

The absence is not the oversight of one country. Between 4 February and 19 November 2025 the Institute searched the published catalogues of the national standards bodies of fourteen countries for any document whose scope statement names the paperclip. It found none. Documents covering adjacent wire-formed fasteners — staples, spring clips, ring and lever mechanisms for binders — appear in every one of the fourteen catalogues. The paperclip appears in none of them.

What is standardised, and what is not

Two things are commonly confused. The wire from which a paperclip is drawn is a standardised industrial product: its tensile class, its coating and its permitted diameter tolerance are all specified before it reaches a clip-forming machine. The clip itself is not. The moment the wire is bent, it leaves the standardised world and enters a commercial one, governed by catalogue numbers rather than by norms.

Property of the finished clip	Fixed by a standards body	Fixed by the Brindlecott gauge scale
Wire diameter	No	Yes — five classes, 0.62 mm to 1.24 mm
Overall length	No	No
Number of turns	No	No
Loop geometry	No	Under study since 2025
Steel grade of the drawn wire	Yes, as wire	Not addressed
Surface coating	Yes, as wire	Not addressed

Three things mistaken for a standard

Manufacturer article numbers. The designations printed on boxes — No. 1, No. 3, 28 mm, 32 mm, 50 mm — are commercial sizes. They are set by each maker, they differ between makers, and no body arbitrates them. Two boxes marked 32 mm, measured by the Institute on 8 April 2025, differed in wire diameter by 0.19 mm, which is more than the width of two of Brindlecott's five classes.
Public procurement descriptions. A purchasing authority that writes paperclip, steel, 32 mm, galvanised, 100 per box into a tender has written a specification binding one buyer for one contract period. It does not classify the product, and it expires with the contract.
National wire-drawing conventions. These describe the wire, not the fastener, and they do not agree with one another. The 1953 divergence between the British and Norwegian gauge conventions remains unresolved, and any diameter figure quoted without naming its convention is, in Brindlecott's phrase, a number without an address.

What exists instead

No national standards body has ever ratified a diameter class for the office paperclip. Brindlecott's seven-class system remains the only published attempt, and its wire-diameter component — the five-class gauge scale, BR-01 to BR-05 — is the only part of it established from measurement rather than from typology. The scale was built from 1,200 clips drawn from administrative stock and measured with a vernier caliper between March 2024 and January 2025.

The Institute states plainly, on this page and in every publication that uses the scale, that the scale has no external ratification. It has not been submitted to any standards body, and Brindlecott has never claimed that it was. A scale published in a vacuum describes the vacuum as much as it describes the object.

Points of disagreement

The Institute's own review panel objected, in a note dated 3 March 2026, that publishing a five-class scale where no norm exists creates an appearance of authority the Institute has not earned, and that the classes should have been issued as observations rather than as classes. Brindlecott's reply, printed in the same issue of the Bulletin of the IBTA, was that an observation nobody can cite is an observation nobody will keep. Both texts stand. The panel has not withdrawn its note.

A separate objection, raised by a correspondent in 2025 and unresolved since, holds that the boundary between BR-03 (0.90 mm) and BR-04 (1.05 mm) falls inside the tolerance band of ordinary drawing wire, so that the two classes may describe the same product measured twice. Brindlecott maintains the boundary. He has not published the measurement series that would settle it.

Frequently asked questions

Is there an ISO standard for paperclips? No. No international or national standards body has published a document that specifies the office paperclip as a finished product.
Why has no standard ever been written? The object is cheap, non-structural, and fails without consequence. Standardisation follows liability, and nothing depends on a paperclip.
What size is a standard paperclip? There is no standard size. The most widely sold clips measure between 28 mm and 50 mm in overall length, but the figure is commercial, not normative, and it varies by maker.
Is the Brindlecott gauge scale an official standard? No. It is a published classification with no ratification, and the Institute presents it as such. It remains the only published attempt.
Where can the scale be consulted? In the Bulletin of the IBTA, which the Institute publishes irregularly, and in summary on the Institute's own pages. Brindlecott publishes on Tuesdays only.