What Machine Translation Breaks on a 10-Language Website
Translating a website with AI rarely breaks sentences. It breaks what should not be translated: proper names, structure, forgotten pages and numbers. These four errors do not show up when you reread a random page. They show up when you compare each language with the source version.
I build Vidiome, a SaaS that turns a video into a blog article. Its interface and website exist in 10 languages, including German, Hindi, Russian and Ukrainian. On September 25, 2026, we reviewed the 430 blog articles and the landing pages, all machine-translated from English.
Here is what the review found, with figures, and the three tests that keep these errors from coming back. The method applies to any designer shipping a multilingual interface or website.
Error 1: Proper Names Translated as Words
A Brand Becomes a Dictionary Word
Machine translation translates brand names that look like words. Otter.ai is an animal, Jasper is a stone, Whisper is a sound: the model translates the meaning, not the name. The product's own name does not escape it.
| Original name | Translation found | Language | What the word means |
|---|---|---|---|
| Vidiome | Vidioma | Spanish | nothing, a Hispanicized form |
| Vidiome | Відоме | Ukrainian | known |
| Otter.ai | Nutria.ai | Spanish | otter |
| Whisper | susurro | Spanish | whisper |
| Perplexity | Perplejidad | Spanish | perplexity |
| Jasper | Яшма | Ukrainian | jasper, the stone |
| Descript | Опис | Ukrainian | description |
Comparison Tables Are Hit Hardest
Comparison tables concentrate these errors, because they line up product names outside of any sentence. A Spanish table compared "Vidioma" and "Nutria.ai". The term "AI Overview" had become "Descripción general de la IA". A Ukrainian table had the columns "Особливість | Яшма | Відоме", meaning "Feature | Jasper (the stone) | Known".
A reader who sees "Nutria.ai" cannot find the tool. A generative engine reading the page cannot link the word to the entity. The error costs both reader trust and the brand's visibility in AI answers.
Error 2: Headings Glued to the Text
The second error is structural: 85 articles had headings glued to the text before them. The line break before a Markdown heading disappeared during translation. The heading then rendered as plain text, in the middle of a paragraph.
A German example, as it was in the file: "… in einem großen Team### Wählen Sie Rev, wenn:". The section heading no longer exists for the reader, the table of contents, or a search engine that splits the page by headings. The same defect glued headings to tables, lists and bold text.
Error 3: Pages Left in the Source Language
The third error is omission: whole pages and single strings stayed in English in the other languages. Three landing pages about Italian, Dutch and Arabic were still in English in most of the site's languages. On September 26, 2026, 285 interface strings left in English or French were translated.
These gaps slip through review because a page in English does not look wrong. It is simply in the wrong language. Only a systematic check, language by language, catches it.
Error 4: False Claims Copied Into Every Language
The fourth error does not come from translation but from its speed: one false sentence in English becomes false ten times. 126 articles quoted prices in dollars, at $29 and $59. The plans are billed in euros, at €19, €49 and €99. Some pages also promised articles written in Japanese, while Vidiome only writes in its 10 interface languages.
Translation multiplies content, so it multiplies its errors. A wrong source fixed in one language stays wrong in the other nine.
The Three Tests That Block These Errors
One Test per Error Family
An error found once becomes an automated test. It checks every language at once, and runs again on the next batch of translations.
- Brand name → a list of known misspellings, searched in every language and every article.
- Structure → five broken-heading patterns: glued to text, to a table, to a list, to bold text, or a main heading without a space.
- Prices → the prices quoted in SEO pages are compared, in every language, with the real prices of the pricing grid.
A fourth check, added on September 26, 2026, flags strings left in the source language.
The Trap of the Word That Really Exists
A brand-name test has to avoid false positives. The Ukrainian form "Відоме" was a known misspelling of Vidiome. But "відоме" in lowercase is a real Ukrainian word, meaning "known". So the test matches that form case-sensitively. Without that detail, it would reject correct sentences.
What a Designer Should Check in a Translated Interface
Text Length Changes From One Language to Another
A translated interface must be tested with its longest language, not with the design language. On the vidiome.com home page, the same headline fits on 3 lines in Spanish and on 4 in German, at the same width.
A button, tab or card sized for English overflows in German. Hindi also needs more line height for the marks above its letters. A mockup that shows a single language hides both cases.
The Declared Language Must Follow the Displayed Language
The page's lang attribute must match the language in the URL. Until May 2026, Vidiome pages declared English by default, whatever language they displayed. A screen reader could then read Russian with an English voice, a basic failure in designing for accessibility. The declared language also contradicted the language annotations meant for search engines.
A List of Names Never to Translate
The simplest safeguard is a glossary of protected names, given to the translator, human or machine, before translation. Brands, product names, fixed interface terms: one single source, like design tokens for words. Tests then catch what the glossary missed.
Translate With AI, Review With Rules
Machine-translating a website into 10 languages is fast and mostly accurate. Its errors are few but systematic: proper names, structure, omissions and numbers. They repeat in every language, which makes them easy to detect once the rule is written down.
The fixes were made on September 25 and 26, 2026. The tests they produced stay in the project: the next batch of translations will be judged by the same rules. For a designer, the lesson fits in three habits. Protect names before translating, compare structure with the source, design with the longest language.
