x-default.
x-default is a special hreflang value declaring the default page to show when no language version matches the user’s language.
On a site in three languages, which version should be shown when a French-speaking user searches? The set does not answer that, because French is not in it. x-default fills the gap.
The value declares a role rather than a language. So the page it points to still carries its own language declaration separately — a page can be both “the Turkish version” and “the default”.
- There must be only one per set — two defaults create a contradiction.
- Optional — without it the engine makes its own decision.
- Not a redirect instruction — it addresses the search engine only.
- It can be the most widely reachable language, the main market’s language, or a language selection page.
The third item has an important consequence: a correctly configured x-default removes the need for automatic redirection. The search engine already shows the appropriate version.
On this site x-default points to the Turkish root, and the decision is a market preference — the target audience is centred on Türkiye. Every page carries four links: three languages and the default.
Which page is chosen is a strategic decision: the most widely reachable language, the main market’s language, or a language selection page. The third is neutral but adds friction and is usually unnecessary on small sites.
The larger the set, the harder the decision: on a site in seven languages no language is an obvious candidate for the default. At that scale either the most widely reachable language is chosen or a selection page is built.
The decision should be made once and documented with its reasoning — otherwise the argument over “which is the original version” reopens periodically within the team.
- A role, not a language — the page pointed to declares its own language as well.
- One per set — two defaults create a contradiction.
- Not a redirect instruction — it addresses the search engine only.
- Optional — without it the engine makes its own decision.
- Declared in the page and the sitemap together — each is the other’s safeguard.
A note on verification: automated tools check that the declaration EXISTS, not whether it points to the right page. That is a strategic decision and only a human can verify it — which is why its reasoning has to be written down.