Script subtag: naming the letters without naming the country
A script subtag names the writing system rather than a country. It is the right tool for languages written in more than one script, and it is the only tag that tells a reader what the characters on the page will look like. As of 2026-09-22.
| Question | Region subtag | Script subtag |
|---|---|---|
| Which characters will I see? | Only by inference | Answered directly |
| Whose wording is it? | Answered directly | Not answered |
| Does it exclude other markets? | Yes, by naming one | No |
| Is it needed for most languages? | No | No, only where two scripts are in use |
Inclusion rule. The two optional narrowing parts a code can carry, compared on the questions a reader brings to a language list. Order. Fixed order, the reader question first.
1A script tag is broader than a region tag
Naming a script includes every market using it and excludes none of them. Naming a country does the opposite. So for a language written two ways across several countries, the script tag is both more informative and less restrictive.
That combination is rare in tagging, and it is why the script form shows up where it does: a vendor serving readers of one script across several territories has exactly one correct way to say so.
2Where it is genuinely required
Most languages are written one way, and a script tag on them adds nothing. A handful are written in two or more, and for those a code without a script is close to meaningless to a reader who can only read one of them.
Chinese is the case in this register. Serbian, Kurdish and several Central Asian languages have the same property, and none of them is declared by any vendor here, so the question does not arise in the table.
3Why it cannot substitute for a region
Two countries can share a script and differ in vocabulary, formality and measurement conventions. A script tag says nothing about any of that, so a vendor using one has answered the character question and left the wording question open.
The register records the two forms as distinct rather than lumping both under tagged. A reader who wants to know which market a page was written for learns it from one and not the other.
A definition, not a measurement: no vendor figure appears here that is not also in the register. The one language here declared in three forms is read on its own page.
Nearby terms: Region subtag, hreflang attribute. The whole vocabulary is at terms; nothing on this page is a claim about a named product.