diff --git a/app/Livewire/Discover/Search.php b/app/Livewire/Discover/Search.php
index 8ee0f6e..3f50e60 100644
--- a/app/Livewire/Discover/Search.php
+++ b/app/Livewire/Discover/Search.php
@@ -14,7 +14,8 @@ use Livewire\WithPagination;
  * The competitor-discovery search: "who sells honey with a .es domain?" — keyword
  * matches a site's pages via MySQL fulltext (natural language mode, so free-text input
  * never trips a boolean-mode syntax error), TLD filters the site's domain suffix,
- * platform filters its detected server/powered-by/generator signature.
+ * platform filters its detected server/powered-by/generator signature, language
+ * filters by the CDX-reported ISO 639 code of a page's content (e.g. "spa", "eng").
  */
 #[Layout('components.layouts.app')]
 class Search extends Component
@@ -30,6 +31,9 @@ class Search extends Component
     #[Url(as: 'platform', history: true)]
     public string $platform = '';
 
+    #[Url(as: 'lang', history: true)]
+    public string $language = '';
+
     public function updatingKeyword(): void
     {
         $this->resetPage();
@@ -45,12 +49,18 @@ class Search extends Component
         $this->resetPage();
     }
 
+    public function updatingLanguage(): void
+    {
+        $this->resetPage();
+    }
+
     public function render(): View
     {
         $keyword = trim($this->keyword);
         $tld = strtolower(trim(ltrim($this->tld, '.')));
         $platform = trim($this->platform);
-        $hasQuery = $keyword !== '' || $tld !== '' || $platform !== '';
+        $language = strtolower(trim($this->language));
+        $hasQuery = $keyword !== '' || $tld !== '' || $platform !== '' || $language !== '';
 
         // Without any filter this would just be the full site list — that's what the
         // Sites page is for. Discover only returns results once you've asked it something.
@@ -73,6 +83,15 @@ class Search extends Component
                             ->orWhere('generator', 'like', '%'.$platform.'%');
                     });
                 })
+                ->when(
+                    $language !== '',
+                    // languages is a comma-separated list of ISO 639 codes (e.g. "spa,eng") —
+                    // FIND_IN_SET matches an exact code, not a LIKE substring match.
+                    fn ($query) => $query->whereHas(
+                        'pages',
+                        fn ($pageQuery) => $pageQuery->whereRaw('FIND_IN_SET(?, languages)', [$language])
+                    )
+                )
                 ->withCount(['pages as matching_pages_count' => function ($pageQuery) use ($keyword) {
                     if ($keyword !== '') {
                         $pageQuery->whereFullText(['title', 'description', 'keywords', 'content'], $keyword);
diff --git a/resources/views/livewire/discover/search.blade.php b/resources/views/livewire/discover/search.blade.php
index ed9e1ac..dc961a5 100644
--- a/resources/views/livewire/discover/search.blade.php
+++ b/resources/views/livewire/discover/search.blade.php
@@ -23,6 +23,12 @@
             placeholder="Platform, e.g. WordPress"
             class="w-full max-w-[14rem] rounded-md border border-neutral-300 px-3 py-2 text-sm focus:border-neutral-500 focus:outline-none dark:border-neutral-700 dark:bg-neutral-900"
         >
+        <input
+            type="text"
+            wire:model.live.debounce.400ms="language"
+            placeholder="Language code, e.g. spa"
+            class="w-full max-w-[12rem] rounded-md border border-neutral-300 px-3 py-2 text-sm focus:border-neutral-500 focus:outline-none dark:border-neutral-700 dark:bg-neutral-900"
+        >
     </div>
 
     <div class="mt-6 overflow-hidden rounded-lg border border-neutral-200 dark:border-neutral-800">
@@ -53,7 +59,7 @@
                             @if ($hasQuery)
                                 No matching sites.
                             @else
-                                Enter a keyword, TLD, or platform to search.
+                                Enter a keyword, TLD, platform, or language to search.
                             @endif
                         </td>
                     </tr>