Many websites that reach people in countries or languages serve different versions of the same content. Hreflang tells search engines about these language variations.
When hreflang is wrong it can confuse search engines and stop them from knowing which URL to show to each market.
Typical issues are missing tags, wrong language or country codes and hreflang URLs that give errors instead of a good page.
What Is Hreflang?
Hreflang is an HTML, HTTP header or XML sitemap annotation that tells search engines about language or regional versions of a page.
For example:
<link rel="alternate" hreflang="en-gb"
href="https://example.com/uk/page">
A U.S. Version might use:
<link rel="alternate" hreflang="en-us"
href="https://example.com/us/page">
The annotations help search engines understand the relationship between these URLs.
Common Hreflang Errors
1. Missing Reciprocal Tags
If Page A references Page B as a version Page B should also reference Page A.
For example:
UK page:
en-gb → UK page
en-us → US page
US page:
en-us → US page
en-gb → UK page
If the relationship is incomplete search engines may not interpret the implementation as intended.
2. Invalid Language or Country Codes
Hreflang values follow language and regional code formats.
For example:
en-us
en-gb
fr-fr
de-de
A common mistake is using incorrectly formatted combinations.
Always validate hreflang values against the ISO language and country conventions.
3. Hreflang URLs Return Errors
An hreflang annotation should point to an URL.
Problems can occur when an annotation points to:
- A 404 page
- A 500 error
- A redirect
- A blocked URL
- A non-canonical version
- A URL that no longer exists
For example:
<link rel="alternate" hreflang="en-gb"
href="https://example.com/uk/page">
If the URL has been removed the hreflang relationship becomes unreliable.
Why Reciprocal Relationships Matter
Hreflang works through relationships between regional or language URLs.
Imagine a website has pages for the UK, United States and Australia.
Each equivalent page should identify the alternatives consistently.
A missing reciprocal relationship can create a hreflang setup and make international targeting less reliable.
Check Every Hreflang URL
A technical SEO crawl should verify that hreflang URLs:
- Return a response
- Are accessible to search engines
- Point to the regional page
- Use hreflang values
- Do not unnecessarily redirect
- Are part of a reciprocal relationship
This is particularly important after website migrations and URL structure changes.
Practical Example
Suppose an international website has:
example.com/us/
example.com/uk/
example.com/au/
The UK page incorrectly references:
en-au → example.com/australia/
But the actual Australian URL is:
example.com/au/
The annotation points to the location and may therefore fail to establish the intended regional relationship.
A crawl can quickly identify this mismatch.
How to Fix Hreflang Problems
Start by creating a map of equivalent regional URLs.
Then:
- Use language and country codes.
- Add annotations.
- Make sure every target URL returns a successful response.
- Remove references to deleted URLs.
- Keep alternatives consistent.
- Re-crawl the website after implementation.
For websites automate hreflang validation, during deployments so new errors are detected before they affect international SEO.
How a Website Audit Helps
A Website Audit Service can check hreflang relationships across multi-regional websites.
An audit can find missing tags, invalid codes, broken target URLs, redirect chains, inconsistent regional mappings and other international SEO problems.
I notice that hreflang can help search engines understand language variations but if hreflang is implemented incorrectly that signal can become weak.
I find the important checks are simple. Use codes, keep reciprocal relationships and make sure every hreflang URL points to an accessible correct page.
Regular technical SEO audits are especially valuable for websites, with hundreds or thousands of regional URLs.
FAQs
What is hreflang used for?
Hreflang helps search engines understand language and regional versions of webpages.
What is a reciprocal hreflang tag?
A reciprocal hreflang tag means the alternative pages reference each other consistently.
Can a 404 URL be used in hreflang?
No. Hreflang annotations should point to accessible URLs.
What happens if hreflang codes are incorrect?
I see that incorrect codes can prevent search engines from interpreting the intended language or regional targeting.
How can I find hreflang errors?
I recommend using a SEO crawler and manually validating important international page relationships.
