Scaling to 10 Languages: Building a Multi-Language Next.js App with next-intl

You shipped your app. Traffic is growing. Then you check analytics and realize 60% of visitors speak a language other than English. Internationalization isn't a nice-to-have — it's the difference between serving your users and losing them. I recently scaled a Next.js application from English-only to 10 languages: English, French, Spanish, German, Portuguese, Japanese, Chinese, Korean, Arabic, and Russian. This article covers architecture decisions, pitfalls, and working code. Why i18n Matters More Than You Think SEO multiplier. Each locale generates its own indexable URLs. 50 pages in 10 languages = 500 indexable URLs, each competing in regional search results. Lower bounce rates. Users who land on content in their native language stay longer and convert better. Why next-intl Library App Router Support Server Components Type Safety next-intl Full Native Excellent next-translate Partial Limited Basic react-intl Partial Requires wrappers Good next-intl was built for the App Router from t