What is Hreflang?
Hreflang is an HTML attribute that tells search engines which language and regional version of a page to show to users in different locations. It prevents duplicate content issues across multilingual sites.
Implementation: Add hreflang tags in the HTML head, HTTP headers, or XML sitemap for every language/region variant of each page.
Format: <link rel='alternate' hreflang='en' href='https://example.com/page' /> <link rel='alternate' hreflang='sv' href='https://example.com/sv/page' />
Critical rules: 1. Hreflang must be bidirectional — if page A references page B, page B must reference page A 2. Include a self-referencing hreflang tag 3. Use x-default for the fallback language/region 4. URL must be fully qualified (absolute, not relative) 5. Language codes must be ISO 639-1 (en, sv, de) and optionally ISO 3166-1 for region (en-US, en-GB)
Common mistakes: missing self-referencing tags, one-directional references, incorrect language codes, and pointing to non-canonical URLs.
Example
Vantacron has English (vantacron.com) and Swedish (vantacron.com/sv) versions. Hreflang tags ensure Swedish users searching Google.se see the Swedish version, while US users see English.