diff --git a/examples/embedded_tab_title.html b/examples/embedded_tab_title.html
new file mode 100644
index 0000000..4d77a84
--- /dev/null
+++ b/examples/embedded_tab_title.html
@@ -0,0 +1,145 @@
+<!doctype html>
+<html lang="en">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>Configurable tab title</title>
+    <link rel="stylesheet" href="../dist-lib/style.css" />
+    <style>
+      html,
+      body {
+        width: 100%;
+        height: 100%;
+        margin: 0;
+      }
+
+      body {
+        display: flex;
+        flex-direction: column;
+        font-family: system-ui, sans-serif;
+      }
+
+      #controls {
+        flex: 0 0 auto;
+        display: flex;
+        align-items: center;
+        gap: 10px;
+        padding: 10px 16px;
+        background: #1e1e1e;
+        color: #eee;
+      }
+
+      #controls input {
+        padding: 6px 8px;
+        border-radius: 6px;
+        border: none;
+        min-width: 220px;
+      }
+
+      #controls button {
+        padding: 6px 12px;
+        border-radius: 6px;
+        border: none;
+        cursor: pointer;
+      }
+
+      #viewer {
+        flex: 1;
+        min-height: 0;
+        position: relative;
+      }
+    </style>
+    <script type="importmap">
+      {
+        "imports": {
+          "vue": "../node_modules/vue/dist/vue.esm-browser.js",
+          "three": "../node_modules/three/build/three.module.js",
+          "three/": "../node_modules/three/",
+          "@gramaziokohler/compas-pb-ts": "../node_modules/@gramaziokohler/compas-pb-ts/dist/index.js",
+          "@bufbuild/protobuf/wire": "../node_modules/@bufbuild/protobuf/dist/esm/wire/index.js"
+        }
+      }
+    </script>
+  </head>
+
+  <body>
+    <!--
+      This bar is just this demo page's own controls, outside the viewer container -
+      it's not part of the library. It lets you retype the title to see the effect
+      live; in a real app you'd normally pass `title` once, up front.
+    -->
+    <div id="controls">
+      <label for="titleInput">Title</label>
+      <input id="titleInput" type="text" value="My Custom Viewer" />
+      <button id="applyButton">Apply</button>
+      <span style="opacity: 0.7">
+        Sets both the browser tab title and the toolbar heading (normally
+        "COMPAS ThreeJs").
+      </span>
+    </div>
+
+    <div id="viewer" aria-label="3D viewer"></div>
+
+    <script type="module">
+      import { createViewer } from "../dist-lib/index.js";
+      import { Box, pbDumpBytes } from "@gramaziokohler/compas-pb-ts";
+
+      const container = document.querySelector("#viewer");
+      if (!(container instanceof HTMLElement)) {
+        throw new Error("Viewer container was not found");
+      }
+
+      const titleInput = document.querySelector("#titleInput");
+      const applyButton = document.querySelector("#applyButton");
+
+      let viewer = null;
+
+      function mountViewer() {
+        viewer?.dispose();
+
+        // `title` is a creation-time option - like toolbarPlacement, it's read once
+        // when the viewer mounts, so applying a new value here recreates the viewer
+        // rather than updating it live. It sets `document.title` and, when the
+        // toolbar is shown, replaces its hardcoded "COMPAS ThreeJs" heading.
+        viewer = createViewer(container, {
+          mode: "embedded",
+          defaultLighting: true,
+          showToolbar: true,
+          title: titleInput.value || undefined,
+          onError(error) {
+            console.error(error.code, error.message, error.details);
+          },
+        });
+
+        viewer.dispatch(
+          pbDumpBytes(
+            new Box({
+              data: {
+                guid: crypto.randomUUID(),
+                name: "Box",
+                frame: {
+                  point: { x: 0, y: 0, z: 0 },
+                  xaxis: { x: 1, y: 0, z: 0 },
+                  yaxis: { x: 0, y: 1, z: 0 },
+                },
+                xsize: 3,
+                ysize: 3,
+                zsize: 1,
+              },
+            }),
+          ),
+        );
+      }
+
+      applyButton.addEventListener("click", mountViewer);
+      titleInput.addEventListener("keydown", (event) => {
+        if (event.key === "Enter") mountViewer();
+      });
+
+      mountViewer();
+      window.addEventListener("pagehide", () => viewer?.dispose(), {
+        once: true,
+      });
+    </script>
+  </body>
+</html>
diff --git a/src/components/layout/Toolbar.vue b/src/components/layout/Toolbar.vue
index bfcc0e0..59ed388 100644
--- a/src/components/layout/Toolbar.vue
+++ b/src/components/layout/Toolbar.vue
@@ -6,7 +6,7 @@
     id="toolbar"
   >
     <h1 class="text-lg font-bold" :class="{ dark: theme.value === 'dark' }">
-      COMPAS ThreeJs
+      {{ toolbarTitle }}
     </h1>
     <TransformGroup />
     <AddObjectGroup />
@@ -29,6 +29,7 @@ import DisplayGroup from "@/components/tools/display/DisplayGroup.vue";
 import {
   isHorizontalPlacement,
   useToolbarPlacement,
+  useToolbarTitle,
   useViewerRuntime,
 } from "@/viewer/viewer_context";
 import { useHover } from "@/composables/useHover";
@@ -43,6 +44,7 @@ const { isHovered } = useHover(toolbarElement);
 const { theme, blockPicker } = useViewerRuntime().store;
 const placement = useToolbarPlacement();
 const isHorizontal = isHorizontalPlacement(placement);
+const toolbarTitle = useToolbarTitle();
 
 watchEffect(() => {
   blockPicker.value = isHovered.value;
diff --git a/src/library/index.ts b/src/library/index.ts
index e59a794..f764548 100644
--- a/src/library/index.ts
+++ b/src/library/index.ts
@@ -7,6 +7,7 @@ import {
   objectActionsPlacementKey,
   openbarPlacementKey,
   toolbarPlacementKey,
+  toolbarTitleKey,
   useViewerRuntime,
   viewerRuntimeKey,
 } from "../viewer/viewer_context";
@@ -48,6 +49,10 @@ export function createViewer(
     );
   }
 
+  if (options.title) {
+    document.title = options.title;
+  }
+
   const runtime = markRaw(new ViewerRuntime(container, options));
   const app = createApp(App, {
     runtime,
@@ -58,6 +63,9 @@ export function createViewer(
   app.provide(toolbarPlacementKey, options.toolbarPlacement ?? "left");
   app.provide(openbarPlacementKey, options.openbarPlacement ?? "left");
   app.provide(metadataPlacementKey, options.metadataPlacement ?? "right");
+  if (options.title) {
+    app.provide(toolbarTitleKey, options.title);
+  }
   app.provide(
     objectActionsPlacementKey,
     options.objectActionsPlacement ?? "right",
diff --git a/src/library/public.d.ts b/src/library/public.d.ts
index 30b8939..d6ff600 100644
--- a/src/library/public.d.ts
+++ b/src/library/public.d.ts
@@ -43,6 +43,8 @@ export interface CompasViewerOptions {
   websocket?: ViewerWebSocketOptions;
   defaultLighting?: boolean;
   showToolbar?: boolean;
+  /** Browser tab title to apply for this viewer instance. Leaves `document.title` untouched if omitted. */
+  title?: string;
   /**
    * Extra toolbar modules mounted after the built-in groups - e.g. a component
    * installed from an npm package. Each module owns its own icons/behavior/ids the
diff --git a/src/library/types.ts b/src/library/types.ts
index 1c5da84..70045c7 100644
--- a/src/library/types.ts
+++ b/src/library/types.ts
@@ -18,6 +18,8 @@ export interface CompasViewerOptions {
   websocket?: ViewerWebSocketOptions;
   defaultLighting?: boolean;
   showToolbar?: boolean;
+  /** Browser tab title to apply for this viewer instance. Leaves `document.title` untouched if omitted. */
+  title?: string;
   /**
    * Extra toolbar modules to mount after the built-in groups - e.g. a `.vue` group
    * installed from an npm package. Each module owns its own icons/behavior/ids the
diff --git a/src/main.ts b/src/main.ts
index 2c05801..6573345 100644
--- a/src/main.ts
+++ b/src/main.ts
@@ -3,7 +3,11 @@ import { createViewer } from "./library";
 const container = document.querySelector<HTMLElement>("#app");
 if (!container) throw new Error("Standalone viewer requires an #app container");
 
+const title =
+  new URLSearchParams(window.location.search).get("title") ?? undefined;
+
 createViewer(container, {
   mode: "websocket",
   showToolbar: true,
+  title,
 });
diff --git a/src/viewer/viewer_context.ts b/src/viewer/viewer_context.ts
index 0928c4e..4b9fadf 100644
--- a/src/viewer/viewer_context.ts
+++ b/src/viewer/viewer_context.ts
@@ -7,6 +7,10 @@ export const viewerRuntimeKey: InjectionKey<ViewerRuntime> = Symbol(
   "compas-viewer-runtime",
 );
 
+export const toolbarTitleKey: InjectionKey<string> = Symbol(
+  "compas-viewer-toolbar-title",
+);
+
 export function useViewerRuntime(): ViewerRuntime {
   const runtime = inject(viewerRuntimeKey);
   if (!runtime) {
@@ -15,6 +19,10 @@ export function useViewerRuntime(): ViewerRuntime {
   return runtime;
 }
 
+export function useToolbarTitle(): string {
+  return inject(toolbarTitleKey, "COMPAS ThreeJs");
+}
+
 /**
  * Which edge of the viewer a panel docks to. Panels sharing an edge stack along it, in
  * a fixed priority order (toolbar, openbar, metadata, objectActions) - see App.vue.