diff --git a/docs/config/env.md b/docs/config/env.md
index a376f685..e207cb87 100644
--- a/docs/config/env.md
+++ b/docs/config/env.md
@@ -72,10 +72,14 @@ See the [WOPI configuration guide](/config/wopi) for details.
 |---|---|---|
 | `OXICLOUD_WOPI_ENABLED` | `false` | Enable WOPI |
 | `OXICLOUD_WOPI_DISCOVERY_URL` | — | Collabora/OnlyOffice discovery URL |
+| `OXICLOUD_WOPI_BASE_URL` | `OXICLOUD_BASE_URL` | URL the editor uses to call OxiCloud's `/wopi/*` endpoints |
+| `OXICLOUD_WOPI_PUBLIC_BASE_URL` | `OXICLOUD_WOPI_BASE_URL` | URL the browser uses to open OxiCloud's WOPI host page and `postMessage` origin |
 | `OXICLOUD_WOPI_SECRET` | (JWT secret) | WOPI token signing key |
 | `OXICLOUD_WOPI_TOKEN_TTL_SECS` | `86400` | Token lifetime |
 | `OXICLOUD_WOPI_LOCK_TTL_SECS` | `1800` | Lock expiration |
 
+When Collabora or OnlyOffice runs on a different hostname, set `OXICLOUD_WOPI_PUBLIC_BASE_URL` to the public OxiCloud URL that the browser can reach. If the editor reaches OxiCloud through a different internal URL, also set `OXICLOUD_WOPI_BASE_URL` for those callbacks.
+
 ## Allocator Tuning
 
 These variables are read directly by **mimalloc**, not by OxiCloud's config parser.
diff --git a/docs/config/wopi.md b/docs/config/wopi.md
index 1238e57a..25a3349e 100644
--- a/docs/config/wopi.md
+++ b/docs/config/wopi.md
@@ -29,10 +29,14 @@ OXICLOUD_WOPI_DISCOVERY_URL="http://collabora:9980/hosting/discovery"
 |---|---|---|
 | `OXICLOUD_WOPI_ENABLED` | `false` | Enable WOPI integration |
 | `OXICLOUD_WOPI_DISCOVERY_URL` | — | Editor's WOPI discovery URL |
+| `OXICLOUD_WOPI_BASE_URL` | `OXICLOUD_BASE_URL` | URL the editor uses to call OxiCloud's `/wopi/*` endpoints |
+| `OXICLOUD_WOPI_PUBLIC_BASE_URL` | `OXICLOUD_WOPI_BASE_URL` | URL the browser uses to open the host page and the `postMessage` origin |
 | `OXICLOUD_WOPI_SECRET` | (JWT secret) | Token signing key |
 | `OXICLOUD_WOPI_TOKEN_TTL_SECS` | `86400` | Access token lifetime |
 | `OXICLOUD_WOPI_LOCK_TTL_SECS` | `1800` | Lock expiration |
 
+If Collabora or OnlyOffice runs on a separate hostname, `OXICLOUD_WOPI_PUBLIC_BASE_URL` should still point to OxiCloud's public URL, not the office URL. Use `OXICLOUD_WOPI_BASE_URL` only when the editor reaches OxiCloud through a different callback URL (for example an internal Docker or cluster address).
+
 ## Docker Compose with Collabora
 
 ```yaml
@@ -68,8 +72,18 @@ services:
     environment:
       OXICLOUD_WOPI_ENABLED: "true"
       OXICLOUD_WOPI_DISCOVERY_URL: "http://onlyoffice/hosting/discovery"
+      OXICLOUD_WOPI_PUBLIC_BASE_URL: "https://cloud.example.com"
+      # Optional when OnlyOffice reaches OxiCloud through a different internal URL.
+      # Otherwise OxiCloud falls back to OXICLOUD_WOPI_PUBLIC_BASE_URL / OXICLOUD_BASE_URL.
+      OXICLOUD_WOPI_BASE_URL: "http://oxicloud:8086"
 ```
 
+In that example:
+
+- the browser loads OxiCloud from `https://cloud.example.com`, so `OXICLOUD_WOPI_PUBLIC_BASE_URL` must use that public OxiCloud URL
+- OnlyOffice calls OxiCloud from the Docker network, so `OXICLOUD_WOPI_BASE_URL` can use `http://oxicloud:8086`
+- if both the browser and the editor use the same OxiCloud URL, you can omit both variables and rely on `OXICLOUD_BASE_URL`
+
 ## WOPI Endpoints
 
 | Method | Endpoint | Description |
diff --git a/example.env b/example.env
index 48a9249a..906425d1 100644
--- a/example.env
+++ b/example.env
@@ -150,6 +150,16 @@ OXICLOUD_WOPI_ENABLED=false
 # Example for OnlyOffice: http://onlyoffice/hosting/discovery
 #OXICLOUD_WOPI_DISCOVERY_URL=
 
+# Public OxiCloud URL used by the browser for the WOPI host page.
+# Keep this on the OxiCloud hostname, even when OnlyOffice/Collabora runs elsewhere.
+# Example: https://cloud.example.com
+#OXICLOUD_WOPI_PUBLIC_BASE_URL=
+
+# Optional callback URL the editor uses to reach OxiCloud's /wopi/* endpoints.
+# Set this only when the editor uses a different internal address than the browser.
+# Example: http://oxicloud:8086
+#OXICLOUD_WOPI_BASE_URL=
+
 # Secret key for signing WOPI access tokens
 # Falls back to OXICLOUD_JWT_SECRET if not set
 #OXICLOUD_WOPI_SECRET=