diff --git a/README.md b/README.md
index 5899df0..9298545 100644
--- a/README.md
+++ b/README.md
@@ -56,6 +56,7 @@ Afterward, the `components` and `target` specified via inputs are installed in a
 | `cache`            | Automatically configure Rust cache (using [`Swatinem/rust-cache`])                     | true          |
 | `cache-workspaces` | Propagates the value to [`Swatinem/rust-cache`]                                        |               |
 | `cache-on-failure` | Propagates the value to [`Swatinem/rust-cache`]                                        | true          |
+| `key`              | Propagates the value to [`Swatinem/rust-cache`]                                        |               |
 | `matcher`          | Enable problem matcher to surface build messages and formatting issues                 | true          |
 | `rustflags`        | Set the value of `RUSTFLAGS` (set to empty string to avoid overwriting existing flags) | "-D warnings" |
 
diff --git a/action.yml b/action.yml
index fa6bd89..16e3b28 100644
--- a/action.yml
+++ b/action.yml
@@ -32,6 +32,9 @@ inputs:
     description: "Also cache on workflow failures"
     default: "true"
     required: false
+  key:
+    description: "An additional cache key that is added alongside the automatic `job`-based cache key and can be used to further differentiate jobs."
+    required: false
   matcher:
     description: "Enable the Rust problem matcher"
     required: false
@@ -181,3 +184,4 @@ runs:
       with:
         workspaces: ${{inputs.cache-workspaces}}
         cache-on-failure: ${{inputs.cache-on-failure}}
+        key: ${{inputs.key}}