We ran the largest hreflang survey ever, astir 10X larger than immoderate different study. In total, we looked astatine issues connected 374,756 antithetic domains that utilized hreflang tags. Our findings amusement that 67% of them person astatine slightest one issue.

Let’s look astatine the astir communal issues you should really care about.

Setting an x-default is not required. But it is recommended if you request a fallback leafage for users whose connection settings don’t lucifer immoderate of your localized versions.

Hreflang works by the astir circumstantial match. Language+country is much circumstantial than conscionable language, which is much circumstantial than x-default. X-default mostly serves arsenic a backup oregon planetary default page, wherever you privation to nonstop people.

Self-referencing hreflang tags are included successful the guidelines. But they’re truly much similar a champion signifier and not really required.

In the aged days of hreflang, earlier the systems and plugins handled it, having a missing self-referencing tag meant that erstwhile you copied the tags to different pages, astatine slightest 1 of the connections would beryllium broken. This is little apt to hap connected modern websites, truthful it’s not arsenic large of an issue.

If you nexus to an incorrect URL, past the tags are breached and pages can’t swap decently successful the hunt results. They enactment successful pairs to signifier a clump of pages. This is what an hreflang clump looks like.

If the breached links are impermanent portion you’re inactive mounting up pages, it’s OK to permission them. If these breached pages don’t beryllium and you don’t program to person them, it doesn’t truly wounded anything—but you whitethorn privation to region the references anyway.

Redirected pages included successful hreflang tags are OK lone if you person an auto-redirecting planetary mentation of the homepage. 

There is an approved setup for homepages lone that uses a 302 redirect for dynamic redirects based connected determination and connection settings. I spot radical effort to alteration this each the time, but it’s a documented setup that has been recommended and moving connected galore sites for years.

In each different situations, a redirected leafage referenced successful hreflang tags volition mean that thing is broken.

As I mentioned, hreflang tags enactment successful pairs. If some pages don’t notation each other, they can’t found the transportation and swap decently successful the hunt results. 

This is particularly important erstwhile you person aggregate versions of a leafage successful the aforesaid language. You whitethorn extremity up sending the idiosyncratic to a mentation of the leafage for the incorrect country.

Hreflang is 1 of galore canonicalization signals that Google uses to find which mentation of a duplicate page it should index. In galore cases I’ve looked at, the canonical tag was ignored successful favour of the URL specified successful hreflang. 

However, this is conscionable a awesome similar galore others and tin beryllium ignored, truthful it whitethorn enactment differently.

Hreflang requires two-letter connection codes (ISO 639-1) and two-letter state codes (ISO 3166-1).

Some of the communal incorrect values are radical utilizing the state codification alternatively of the connection code, typos, trying to usage portion codes erstwhile they aren’t supported, oregon trying to usage three-letter codes alternatively of two-letter ones.

Some radical conscionable usage codes that are incorrect arsenic well. For example, they usage things similar “la” for Latin America, but that doesn’t work. Another communal 1 is “uk” erstwhile they should usage “gb.” But the comic happening present is that “uk” is simply a specially reserved code, and Google really accepts this one!

This contented shows pages with antithetic connection codes declared successful the HTML connection property and hreflang annotation for the URL. 

These are antithetic systems, but some are utilized to accidental what connection the leafage is in. If they don’t match, thing is fishy and you should cheque which connection the leafage is really in.

For an hreflang connection oregon connection and state combination, you should lone person 1 leafage specified for each unsocial value. If you specify “en” for a leafage and usage “en” again but accidental it’s a antithetic page, past Google is going to person to take 1 oregon the other. They can’t some beryllium the close version.

While this sometimes happens successful the codification of the page, it’s often a mismatch betwixt the codification of the leafage and sitemaps. Ahrefs’ Site Audit looks astatine each the supported hreflang implementation locations, including the <head>, HTTP header, and sitemaps.

In this case, pages were referenced for much than 1 connection successful hreflang annotations. For example, you whitethorn spot this contented if you notation the leafage successful an hreflang tag that specifies the leafage is for English and different hreflang tag that says it’s for Spanish.

You shouldn’t person 2 languages connected the aforesaid page, truthful cheque which 1 is close and region the other one.

Final thoughts

A immense acknowledgment and shoutout to my colleague, Oleksiy Golvoko, for helping maine stitchery this data! I’m amazed the numbers weren’t worse successful the study, but I fishy that a batch of these sites person basal implementations.

Hreflang is analyzable and hard to get right. It tin interruption successful truthful galore antithetic ways. Here’s what Google’s John Mueller has to accidental about it.

Want to spot if your tract has hreflang issues? Run it done Site Audit oregon effort it for escaped with Ahrefs Webmaster Tools.

Hreflang is simply a taxable I’m passionate astir and 1 that I’ve written and presented galore times, truthful I was blessed to constitute this up. One of the archetypal blog posts I made edits to erstwhile I joined Ahrefs was our hreflang guide. I’d urge that if you privation to larn much astir hreflang and immoderate of the nuances of it.

If you person questions, connection maine on Twitter.