diff --git a/apps/web/src/api/client.ts b/apps/web/src/api/client.ts
index 3080d05..408ecbc 100644
--- a/apps/web/src/api/client.ts
+++ b/apps/web/src/api/client.ts
@@ -12,8 +12,16 @@ import {
   type ThemePreference,
 } from "@batch-cooking/shared";
 
-/** Base URL of the API, configurable via `VITE_API_URL` (see `.env.example`). */
-const API_BASE_URL: string = import.meta.env.VITE_API_URL ?? "http://localhost:3000";
+/**
+ * Base URL of the API, configurable via `VITE_API_URL` (see `.env.example`).
+ * Defaults to `""` (same origin as the page) — correct for the production
+ * Docker image, where the API serves this very frontend build (see
+ * apps/api/Dockerfile), so a relative path already reaches it. Native dev
+ * (`pnpm dev:web`) overrides this via `VITE_API_URL=http://localhost:3000`
+ * in `apps/web/.env`, since the Vite dev server (5173) and the API (3000)
+ * are on different origins there.
+ */
+const API_BASE_URL: string = import.meta.env.VITE_API_URL ?? "";
 
 /**
  * Thrown by {@link ApiClient} whenever the API responds with a non-2xx