diff --git a/src/lib/components/leaflet/LeafletBskyPost.svelte b/src/lib/components/leaflet/LeafletBskyPost.svelte
index e7542a8..acab672 100644
--- a/src/lib/components/leaflet/LeafletBskyPost.svelte
+++ b/src/lib/components/leaflet/LeafletBskyPost.svelte
@@ -1,4 +1,6 @@
 <script lang="ts">
+  import { blueskyPostUrl } from "$lib/utils/bluesky";
+
   /**
    * LeafletBskyPost — rendered Bluesky post embed from a Leaflet document.
    * Converts the at:// URI into a bsky.app profile/post URL and links
@@ -10,18 +12,7 @@
     clientHost?: string;
   } = $props();
 
-  const BSKY_HOST = "bsky.app";
-
-  function getEmbedUrl(): string {
-    const host = clientHost?.replace(/\/$/, "") || `https://${BSKY_HOST}`;
-    // at-uri: at://did:.../app.bsky.feed.post/rkey
-    const parts = postRef.uri.replace("at://", "").split("/");
-    const did = parts[0];
-    const rkey = parts[parts.length - 1];
-    return `${host}/profile/${did}/post/${rkey}`;
-  }
-
-  let embedUrl = $derived(getEmbedUrl());
+  let embedUrl = $derived(blueskyPostUrl(postRef.uri, clientHost));
 </script>
 
 <div class="leaflet-bsky-post">
diff --git a/src/lib/utils/bluesky.ts b/src/lib/utils/bluesky.ts
new file mode 100644
index 0000000..50b7ad1
--- /dev/null
+++ b/src/lib/utils/bluesky.ts
@@ -0,0 +1,30 @@
+const DEFAULT_BLUESKY_CLIENT = "https://bsky.app";
+
+function blueskyClientUrl(clientHost?: string): string {
+  const configuredHost = clientHost?.trim();
+  if (!configuredHost) return DEFAULT_BLUESKY_CLIENT;
+
+  try {
+    const url = new URL(
+      /^https?:\/\//i.test(configuredHost)
+        ? configuredHost
+        : `https://${configuredHost}`,
+    );
+
+    if (url.protocol !== "http:" && url.protocol !== "https:") {
+      return DEFAULT_BLUESKY_CLIENT;
+    }
+
+    return url.href.replace(/\/$/, "");
+  } catch {
+    return DEFAULT_BLUESKY_CLIENT;
+  }
+}
+
+export function blueskyPostUrl(atUri: string, clientHost?: string): string {
+  const parts = atUri.replace(/^at:\/\//, "").split("/");
+  const did = parts[0];
+  const rkey = parts.at(-1);
+
+  return `${blueskyClientUrl(clientHost)}/profile/${did}/post/${rkey}`;
+}