Hreflang Audits for Global Websites: How KWT Spider and Screaming Frog Identify International SEO Issues
By kwt spider 07-10-2026 21
Running a website across multiple countries or languages introduces a different layer of technical SEO. A company may have separate pages for English-speaking users, German customers, French audiences, or different regional markets, but search engines still need clear signals about which version belongs to which audience. This is where hreflang becomes important.
Hreflang annotations help search engines understand the relationship between localized versions of a page. When implemented correctly, they can help search engines serve a more appropriate regional or language version to users.
For larger international websites, however, checking hreflang manually can quickly become difficult. A single missing attribute, incorrect language code, or broken return reference can affect many URLs.
This is where technical SEO crawlers such as KWT Spider and Screaming Frog can become useful.
What Is Hreflang?
Hreflang is an HTML attribute and link relationship used to indicate alternative versions of a webpage intended for different languages or regions. For example, a website might have:
- example.com/en/
- example.com/fr/
- example.com/de/
The site can use hreflang annotations to indicate which version is intended for English, French, or German-speaking users. A regional implementation can be even more specific. A business might have separate English-language pages for users in the United States and United Kingdom. The purpose is not to tell search engines to rank one page higher than another. Instead, hreflang provides information about the relationship between alternate versions. That distinction is important when auditing international websites.
Why Hreflang Audits Matter
Usually hreflang implementations have multiple URLs pointing to each other. That creates more chances for technical mistakes. For example, a website might have an English page that references a French alternative, but the French page does not reference the English version. Another common mistake is using the wrong language or region code.
Also, there can be problems like:
- Hreflang URL is returning 404 status.
- A page points to itself incorrectly.
- Cannot crawl alternate URLs.
- Two localized pages refer to different versions of each other.
- Hreflang annotations are not defined for some templates.
- Incorrectly formatted language and country codes.
- Canonical tags conflict with the intended international setup.
These issues can be difficult to detect on a site with thousands or millions of localized URLs.
How KWT Spider integrates into an international SEO audit
KWT Spider can be used as part of a technical crawl to analyze international SEO signals in combination with other page level information. Instead of checking each URL for hreflang, the SEO pro can look at the crawl to see patterns across the site. For example, a crawl can help bring attention to localized URLs that have unexpected status codes, indexing issues, broken links, or other technical problems. This is useful because hreflang is seldom used on its own outside of the rest of the architecture of the site. An international SEO problem could actually start with a URL that returns the wrong status code, a canonical that points somewhere it shouldn’t, or a localized page that no longer exists. KWT Spider’s broader technical SEO workflow means that these signals are taken into account together.
Hreflang and Canonical Tags Have to Work Together
Hreflang and Canonicalization Relationship – One of the areas that need special attention during an international SEO audit. Think of a website with English, French and German versions of the same product page. Each version should have a well defined canonical strategy. At the same time, hreflang should tell about the relationship between localized versions. These are different signals, with different objectives. A canonical tells search engines which URL should be considered the preferred version of a duplicate or substantially similar page. Hreflang informs search engines of alternate language or regional versions. They should therefore not be interchangeable, but jointly audited. A crawler can help you identify cases where these signals do not appear to align with the intended architecture of the site.
How Screaming Frog can help Hreflang
Screaming Frog is also commonly used for international SEO audits and can help SEO professionals investigate hreflang implementations across a crawl. Its crawling workflow allows the investigation of relationships between URLs and the discovery of technical patterns that would be cumbersome to investigate manually on a large website. This can be especially useful for an international website where localized versions are generated through different templates or CMS systems. An SEO professional can take the crawl and validate that hreflang implementations are consistent, and then drill down to specific URLs where something looks amiss. The value is more than simply finding an error. It’s in knowing how that error fits into the larger architecture of the website.
Common Hreflang Mistakes to Look Out For
Missing References Hreflang
Some localized pages may have hreflang implemented, and some may not. This can happen after a redesign, migration, or adding a new regional website. A crawl can help find template inconsistencies.
Alternate URLs Broken
A hreflang annotation can point to a URL that doesn’t exist. The implementation should be reviewed if the page referenced returns a 404 or some other unexpected status code.
Return reference not found
Internationally implementations generally work through alternative page relationships. For example, the English page can link to the French version, and the French version should link back to the English version. Missing return references is an important audit area.
Wrong Language Codes
Hreflang uses language and regional specific tags. Annotation might be useless if format is not correct. This can be especially helpful for websites that have multiple regional variations of the same language. For example, English for the United States and English for the United Kingdom are different regional targeting situations.
Conflicts of Canons
A localized page may contain a canonical pointing somewhere that does not fit the intended international structure. This can cause mixed signals and should be considered in the same audit.
Low indexability alternate pages
If a hreflang reference points to a page that is blocked from indexing or otherwise not available to search engines, the implementation needs to be reviewed carefully. This is another reason why hreflang should be audited alongside indexability.
Hreflang Language vs. Country Targeting
Regarding international SEO, a key question is whether a site is targeting a language, a country, or both. Language code Indicates the language. Regional codes can target a specific geographical audience. For example, a company may offer Spanish content for a general Spanish-speaking audience or another version for users in Spain. The implementation should reflect the actual content and audience strategy of the site. Just because country codes exist doesn't mean they are necessarily useful. The technical set up should reflect the real international structure of the site.
KWT Spider and Large International Sites
International sites can get huge. A company may have thousands of products and dozens of markets and multiple language versions for each market. This means that there are plenty of URLs to review when an international SEO problem arises. This is where desktop crawling can help. KWT Spider supports large crawl workflows and SQLite Database Mode to deal with large datasets locally. This mode is optimized for crawls of 50,000+ pages by streaming crawl records to local storage rather than forcing the entire dataset to reside in memory. This offers a practical way for agencies and SEO teams to investigate large URL sets without reducing the audit to a small sample, which is especially useful for large international websites.
Hreflang & Website Migrations
Website migrations often cause international SEO issues.
A company can change.
- URL Structures
- Domains
- Subdomains
- Country Folders
- CMS platforms
- Tradutores
- Internal linking architecture
If the hreflang references are not updated during the migration, the old URLs may still exist in the implementation. This can set off a chain of problems. A German page, for example, may still refer to an old French URL that has been removed in the migration. A post-migration crawl can help to identify these. The new website can be crawled by KWT Spider and the resulting technical signals analyzed. Screaming Frog is another established desktop-crawling option for the same type of verification.
A Practical International SEO Audit Workflow
A good hreflang audit doesn’t have to start by manually checking every annotation.
To begin, examine the international layout of the website.
Find the different countries, languages, domains, subdomains, directory structures etc.
Then crawl the relevant sections.
Look for unexpected status codes, redirects, missing pages, canonical issues, and indexability issues.
Then check the hreflang implementation itself.
Ensure that the localized versions point to the correct alternatives and that the relationships are consistent.
Then look at the pages where the problems are.
Often it is more useful to find a pattern affecting 5,000 URLs than to fix one isolated annotation.
Finally, validate major changes and continue to monitor post-deployment.
Don’t Use Hreflang as a Ranking Hack
Hreflang is helpful, but it should not be viewed as a way to directly boost rankings. It seeks to communicate language and regional relationships across pages. A technically perfect hreflang implementation can’t make up for bad localized content. If a French page is just an automated translation with little value for French users, adding hreflang doesn't fix that problem. International SEO still means good content, proper localization, good site architecture and proper technical implementation. Hreflang is one piece of that bigger puzzle.
KWT Spider adds value where
The great thing about KWT Spider in this workflow is that it allows us to see international SEO signals within the framework of the overall technical health of a site. That's important because international SEO issues often overlap. An hreflang reference can point to a redirected URL. A canonical problem can be a localized page. Internal links in a regional section may be broken. A translated template can have inconsistent metadata. More context than just hreflang is provided when combining these signals. KWT Spider's local-first desktop approach could also be a good fit for agencies and SEO teams who like to have their crawl data on their own machines. It has native Windows, macOS and Linux builds so it can work into various desktop-based SEO workflows.
Where Screaming Frog Fits In
Screaming Frog remains a solid choice in terms of international technical SEO crawling. Its crawling capabilities make it a good tool for exploring large websites, URL relationships, redirects, canonicals, links and other signals that are important to international SEO. If you are already using Screaming Frog it can be a great base for hreflang auditing. Another desktop option is KWT Spider, especially for teams who want to combine their traditional technical SEO crawling with its broader GEO and AI-search-readiness analysis. At the end of the day this decision is up to the team’s existing workflow, the needs of the website and the kind of analysis they want to do.
International SEO: It's More Than Just Hreflang
Correct annotations are not enough for a successful international website.
SEO teams should also think about:
- Quality of translated content
- Interconnection
- Canonicalization
- XML Sitemap
- Indexing pages
- URL structure
- Meta data
- Data in a structured format
- Re-directs
- Business information.
- Regional user experience
Hreflang is just one piece of this larger puzzle. A crawler like KWT Spider can help aggregate many of these technical signals, which can make it easier to understand if a problem is isolated or part of a larger architectural problem.
Conclusion
International SEO is complex, and the more countries and languages a website adds, the more complex it gets. Hreflang tells search engines how localized versions of pages relate to one another, but if done incorrectly, can create confusing technical signals. That’s why regular audits are important.” Screaming Frog has a well-established desktop crawling workflow that you can use to examine hreflang and other international SEO signals. KWT Spider offers an alternative, combining technical crawling with wider diagnostics and AI-search-readiness considerations. If you’re a team managing international websites, KWT Spider is worth looking at if you want to look at hreflang in conjunction with indexability, canonicalization, links, status codes, structured data and other technical signals, all in one desktop workflow. The goal isn’t just to make hreflang tags pass an audit. The idea is to have a clear international website structure that search engines can read and users can use easily.
FAQs
What is hreflang used for?
Hreflang helps search engines understand which language or regional version of a webpage is intended for a particular audience.
Can KWT Spider audit international SEO issues?
KWT Spider can be used to investigate technical signals relevant to international SEO, including URL status, indexability, links, canonical signals, and other page-level information as part of a crawl.
Can Screaming Frog check hreflang?
Yes. Screaming Frog can be used to crawl international websites and investigate hreflang implementations alongside other technical SEO signals.
What happens if hreflang points to a broken URL?
The implementation should be reviewed because the referenced alternate page is no longer available at the specified URL. A crawl can help identify these broken references.
Should hreflang and canonical tags be audited together?
Yes. They serve different purposes, but reviewing them together can help identify conflicting or unexpected international SEO signals.
Is hreflang important for AI search?
Hreflang is primarily an international SEO signal rather than an AI-search ranking factor. However, clear language and regional signals are part of making a website's structure understandable to search systems.
Is KWT Spider available for international SEO audits on Mac and Linux?
Yes. KWT Spider provides native builds for Windows, macOS, and Linux, allowing international SEO teams to run desktop crawls across different operating systems.
