Free international SEO audit: Your languages, hreflang tags and translations, checked page by page

You translated your website into 3 languages. Yet a buyer in Germany still lands on your English page. An international SEO audit tells you why, and our free hreflang checker shows you what to fix.

The cause is often small. A missing return link or a wrong region code is enough. So is a canonical tag that points to the English page. Google then ignores your tags or misses your translated pages.

Most of these errors are easy to fix once you see them. Enter your website address in the tool above. You get a score out of 100, a list of errors with examples from your website, and the corrected hreflang tags of your home page.

What is international SEO?

International SEO helps search engines show the right version of your website to each visitor. It covers 3 things: your URL structure, your hreflang tags and the quality of each translated page.

International SEO vs multilingual SEO

Multilingual SEO is about languages. International SEO also targets countries, sometimes with one language for several countries. A website in English, French and German does multilingual SEO. A website with one page for France and another for Canada, both in French, does international SEO, because the region matters. Both rely on the same basics: separate URLs, hreflang tags and well translated content.

When you need it

You need it as soon as your website has 2 languages or targets 2 countries. Watch for these signs:

• visitors in one country see the wrong language in search results;
• your translated pages bring in little organic traffic;
• you plan to open a new market and want the structure right from day 1.

If your website exists in one language only, the tool tells you and lists the steps to open a 2nd language.

Which structure for a multilingual website?

Google recommends a separate URL for each language. It advises against using a cookie or browser detection to switch languages at the same URL. It also advises against redirecting visitors automatically based on their presumed language. Googlebot usually crawls from the USA without a language preference, so it might never reach your other versions.

The simplest choice for most websites

For most websites, subfolders are the easiest option to run. You keep one domain and one CMS, and each language sits in a clear folder like /fr/ or /de/. Choose country domains if you run a separate business in each country. Whatever you choose, add a language switcher on every page, with links to the other versions, as Google advises.

Hreflang tags explained simply

Hreflang tags tell Google which pages are versions of the same content in other languages. Google can then show each searcher the version in their language and for their country.

The value starts with a language code in ISO 639-1 format, like en, fr or de. You can add a region code in ISO 3166-1 alpha-2 format, like en-GB or fr-CA. A region alone is not valid. Google also ignores reserved codes such as UK, EU or UN, so use GB for the United Kingdom.

Lumen Studio is a fictional website at lumen-studio.example, in English, French and German. Its English home page carries this block in the head:

<link rel="canonical" href="https://lumen-studio.example/en/" />
<link rel="alternate" hreflang="en" href="https://lumen-studio.example/en/" />
<link rel="alternate" hreflang="fr" href="https://lumen-studio.example/fr/" />
<link rel="alternate" hreflang="de" href="https://lumen-studio.example/de/" />
<link rel="alternate" hreflang="x-default" href="https://lumen-studio.example/" />

The French and German pages carry the same hreflang tags. Only their canonical changes, because it points to the page itself: the French page has a canonical to https://lumen-studio.example/fr/ and never to /en/. Each version lists itself and all the others. If 2 pages don't point to each other, Google ignores the link between them.

The 3 ways to declare hreflang

Google accepts 3 equivalent methods:

• link tags in the head of each page;
• HTTP headers sent by your server;
• your sitemap, with each URL and its versions listed together.

Pick one method per website. Your team then keeps a single place to update.

What x-default is for

x-default marks the fallback page. Google shows it when none of your languages matches the browser settings. Google recommends it for language selector pages, like the root page of Lumen Studio.

The 7 most common hreflang errors

The tool looks for each of these errors on the pages it reads.

1. Missing return links. If the English page points to the French page, the French page must point back. Otherwise Google ignores the link between these 2 pages.
2. A page that doesn't list itself. Each version must include its own URL in the block.
3. Invalid codes. UK is a reserved code, so write en-GB instead of en-UK. Use a hyphen too, so en_US becomes en-US.
4. Relative URLs. Write https://lumen-studio.example/fr/ in full, never /fr/ alone.
5. Target pages that redirect or return 404 or noindex. A best practice rather than a written Google rule: point each link straight to the final page, open to search engines.
6. A canonical pointing to another language. If the German page has a canonical to the English page, it contradicts your hreflang tags.
7. A page declared in one language but left in another. Google uses neither hreflang nor the lang attribute to detect the language. It reads the visible content, so a /de/ page written in English counts as English.

Website localization and SEO: translating is not enough

Website localization adapts your content to each market. People search with different words from one country to the next. So research your keywords in each language, starting from local searches.

Keep a glossary of your brand terms. Without it, the same product name ends up translated 3 ways across your pages. Then have every translation reviewed by someone who knows the market.

Watch Google's policy too. Since March 2024, its scaled content abuse policy targets pages produced at scale through automated transformations, translation included, when they bring little value to visitors. And if you translate only the template, the experience suffers: a German menu above an English article won't help a German buyer.

Mark AI translates and adapts your content in each language, in your brand voice and with a glossary your team approves. Its agents apply your key terms the same way on every page. Your team reviews every page in the platform, and nothing goes live without their approval.

How to run an international SEO audit with the free hreflang checker

1. Enter your website address. You don't need to sign up.
2. Let the tool read your website. It reads your home page and its language versions, your robots.txt and your sitemap, then a few inner pages: up to 20 pages in total.
3. Get the diagnosis. The tool finds your languages and your structure: subfolders, subdomains, separate domains or URL parameters. It checks each hreflang rule above, the canonical of each page, the lang attribute and the language of the text. It counts the pages of each language in your sitemap and estimates the pages and words left to translate.
4. Review the translation and fix your tags. An AI compares your home page with its translation and flags untranslated passages, missing sections and key terms translated in several ways. You also get the corrected hreflang tags of your home page, ready to paste.

How to read your score

Your score out of 100 covers 4 areas:

• Structure (20 points): one URL per version, a language switcher, no automatic redirect.
• Hreflang tags (40 points): valid codes, self references, return links, x-default and full URLs.
• Consistency (20 points): each canonical points to its own page, and each version is written in its announced language, with the right lang attribute.
• Coverage (20 points): how much of your website is translated in each language, from your sitemap.

The tool works as a hreflang checker and a hreflang validator. Use it as a hreflang tester each time you change your tags. For your home page, it also acts as a hreflang tag generator, because it writes the corrected block for you: you don't need a separate hreflang generator for that page.

The checklist before you launch a new language

1. Choose one structure and give each language its own URL.
2. Translate the full content, along with the menus and footer.
3. Research keywords in the new language.
4. Add the new language to your brand glossary and get it reviewed.
5. Add hreflang tags on every version, with a self reference and return links.
6. Use valid codes, fully qualified https URLs and an x-default.
7. Point each canonical to the page itself, and check that target pages answer without a redirect or noindex.
8. Add a language switcher, update your sitemap and avoid automatic redirects.

How to apply this today

1. Run the free audit on your website address and write down your score.
2. Fix missing return links and self references first.
3. Replace invalid codes, such as en-UK with en-GB.
4. Paste the corrected hreflang tags on your home page and its versions, then apply the same pattern to your other pages.
5. Check that each canonical points to the page itself.
6. Build a glossary of your key terms and have it reviewed in each country.

International SEO audit: frequently asked questions