methodology / SEO & Discoverability / #42
hreflang for multi-language sites
#42 · Recommended · Web Quality · weighted · SEO & Discoverability · weight 0.7% · impl implemented · method v1.2.0
Web Quality factor
This factor is part of Web Quality — the weighted 0..100 score that sits above Web Standards. Its weight depends on what kind of site is being measured. Web Standards items take priority; this factor only enters the score once Web Standards passes.
- Base weight
- 0.5 applied to every site type unless overridden below
- Why this weight
- hreflang — only matters for multi-language sites. Connector emits n/a when monolingual.
What this means for your business
If you serve customers in more than one language or country, your site needs to tell Google which version is for whom. Otherwise a Spanish-speaking customer might land on your English page and bounce.
Plain title: Telling Google which language a visitor should see
What we measure
If your site serves multiple languages or regions, hreflang tells Google which version to show whom. Without it, Google guesses and often gets it wrong.
How to improve your score
Add `<link rel="alternate" hreflang="...">` tags pointing at each language version, including a self-reference and an `x-default` fallback.
Facts
Implementation notes
Detect alternate hreflang links in the head and HTTP headers; flag missing or asymmetric pairs.
Scoring
Scoring formulas are versioned with the methodology. The current method (v1.2.0) maps raw measurements to pass, warn, fail. Factor weights determine how much each contributes to the composite — see the methodology index for the full table.
Cited by these standards
Standards in the Standards Library whose satisfiedBy requirement tree references this factor. Each link goes to the standard's full entry — methodology, scope, and the other factors it relies on.
Version history
| Version | Change | Date |
|---|---|---|
| v1.2.0 | Factor introduced. Status: live. Scoring impl: implemented. | 2026-04-28 |