Making a WordPress block theme site multilingual should not take a weekend and a yearly license. I built Blocklingo to translate a whole block theme site with AI - pages, menus, header, footer and SEO - with your own API key and no subscription.
Why I built it
I build sites on block (FSE) themes for clients, and every multilingual project hit the same wall. The established plugins were designed for classic themes and page builders. On a block theme you end up fighting them: the header and footer stay in one language, navigation menus need workarounds, and machine translation is either an extra paid add-on or breaks block markup.
The result is a yearly license, hours of manual copy-pasting, and a client asking why the footer on /uk/ is still in English. I wanted a plugin that treats Gutenberg as the main use case, not an afterthought.
What Blocklingo is
Blocklingo is a free WordPress plugin that makes a block theme site multilingual and translates it with AI. You bring your own key from Google, DeepL, Gemini or Claude - or, on WordPress 7.0+, use the AI provider already set up in Settings > Connectors with no extra key.
It keeps the familiar model: one post per language, linked in a translation group. The default language has no URL prefix, others live under /uk/, /de/ and so on.
It is a good fit if you are:
- a freelancer or agency shipping block theme sites to clients in two or more languages
- a site owner who wants the whole site translated today and reviewed tomorrow, not typed by hand
- a developer who wants clean hooks and no lock-in: deactivate it and your content stays as normal posts and pages
Key features
AI translation that keeps blocks valid. In the block editor, block attributes are translated in the browser and re-serialized, so you never get the "This block contains unexpected content" warning. A glossary keeps brand names untouched, and shortcodes are never sent to translation.
Translate everything in one click. Categories, tags, menus, header, footer, pages and posts are machine-translated into a language as drafts for review. It shows the time left, pauses after 3 failures in a row, and stops with a clear message if the key is rejected or the account is out of credit.
Header, footer and menus per language. A Ukrainian copy of the header (header-uk) replaces the default one on /uk/ pages. Navigation menus and synced patterns follow the page language too.
SEO out of the box. Titles and descriptions from Slim SEO, Yoast, Rank Math and SEOPress are translated. Hreflang tags, per-language locale and a sitemap with alternates are added for you.
Language strings. Theme and plugin texts without an official translation are collected while you browse and translated by hand or by machine - like WPML String Translation, built in.
The small things that save hours.
- Language switcher as a block, a shortcode, a template tag, or added to a classic theme menu without code
- Latin slugs for Cyrillic titles, with redirects from the old addresses
- Official WordPress, theme and plugin language files installed automatically
- Errors in plain words with a "Show technical details" toggle, not a broken JSON response
- Nothing is sent to any service in the background or when visitors browse
Blocklingo vs Polylang Pro vs WPML
Blocklingo costs nothing for the plugin; you pay only your translation provider, and Google, DeepL and Gemini have free allowances.
| Blocklingo | Polylang Pro | WPML | |
|---|---|---|---|
| Price, 1 site (per year) | Free | €99 | €39 (Blog) / €99 (CMS, 3 sites) |
| Machine translation | Google, DeepL, Gemini, Claude, WordPress AI | DeepL (own key) | WPML credits; 22,500 words included in CMS |
| Built for | Block (FSE) themes first | Classic and block themes | Classic themes and page builders |
| String translation | Included | Included | Included in CMS |
Prices from Polylang and WPML, checked October 2026. Provider API usage is billed by the provider you choose.
To be fair: Polylang and WPML are mature, with large ecosystems and WooCommerce support. If your site runs on Elementor or WooCommerce today, they are the safer choice. If it runs on a block theme, Blocklingo was made for it.
Get started
- Install Blocklingo from wordpress.org and activate it. Existing content is assigned to your default language; nothing else changes.
- Go to Settings > Blocklingo, add a language and pick a translation provider.
- Press "Translate everything into ...", then review and publish the drafts.
- Add the Language switcher block to your header in the Site Editor.
The step-by-step version with screenshots is in How to translate a block theme site with AI.
Blocklingo is free and actively developed. If you hit a bug or miss a feature, use "Contact the developer" in the plugin or write to me. Need a multilingual site built or migrated from WPML or Polylang? I do that too.