diff --git a/headroom/dashboard/templates/dashboard.html b/headroom/dashboard/templates/dashboard.html
index 168fa73e2..1aa01f8cb 100644
--- a/headroom/dashboard/templates/dashboard.html
+++ b/headroom/dashboard/templates/dashboard.html
@@ -1180,7 +1180,7 @@ <h1 class="text-xl font-semibold tracking-tight">HEADROOM</h1>
                     <div class="text-xs text-gray-500 mb-3">No per-project data yet.</div>
                     <div class="text-xs text-gray-600 font-mono leading-relaxed">
                         Add to each project's <span class="text-gray-400">.claude/settings.local.json</span>:<br>
-                        <span class="text-accent">ANTHROPIC_BASE_URL: http://127.0.0.1:8787/p/&lt;project-name&gt;</span>
+                        <span class="text-accent" x-text="'ANTHROPIC_BASE_URL: ' + window.location.origin + '/p/<project-name>'"></span>
                     </div>
                 </div>
             </template>
diff --git a/tests/test_dashboard_cache_ttl_playwright.py b/tests/test_dashboard_cache_ttl_playwright.py
index 7144aa55b..a2ae2ad88 100644
--- a/tests/test_dashboard_cache_ttl_playwright.py
+++ b/tests/test_dashboard_cache_ttl_playwright.py
@@ -187,6 +187,39 @@ def handler(route) -> None:  # type: ignore[no-untyped-def]
     page.route("**/*", handler)
 
 
+def test_dashboard_per_project_setup_url_uses_current_origin() -> None:
+    with sync_playwright() as pw:
+        browser = pw.chromium.launch()
+        page = browser.new_page(viewport={"width": 1720, "height": 1400}, color_scheme="dark")
+        _install_dashboard_routes(page)
+
+        page.goto("http://127.0.0.1:8788/dashboard", wait_until="load")
+        expect(
+            page.get_by_text(
+                "ANTHROPIC_BASE_URL: http://127.0.0.1:8788/p/<project-name>", exact=True
+            )
+        ).to_be_visible()
+        expect(
+            page.get_by_text(
+                "ANTHROPIC_BASE_URL: http://127.0.0.1:8787/p/<project-name>", exact=True
+            )
+        ).to_have_count(0)
+
+        page.goto("http://headroom.local:9393/dashboard", wait_until="load")
+        expect(
+            page.get_by_text(
+                "ANTHROPIC_BASE_URL: http://headroom.local:9393/p/<project-name>", exact=True
+            )
+        ).to_be_visible()
+        expect(
+            page.get_by_text(
+                "ANTHROPIC_BASE_URL: http://127.0.0.1:8787/p/<project-name>", exact=True
+            )
+        ).to_have_count(0)
+
+        browser.close()
+
+
 def test_dashboard_renders_observed_ttl_metrics_and_can_capture_screenshot() -> None:
     artifact_dir = os.environ.get("HEADROOM_PLAYWRIGHT_ARTIFACT_DIR")