diff --git a/action.yml b/action.yml
index b050545..e5cb1f3 100644
--- a/action.yml
+++ b/action.yml
@@ -6,9 +6,6 @@ branding:
   color: purple
 
 inputs:
-  toolchain:
-    description: Rust toolchain specification -- see https://rust-lang.github.io/rustup/concepts/toolchains.html#toolchain-specification
-    required: true
   targets:
     description: Comma-separated list of target triples to install for this toolchain
     required: false
@@ -41,11 +38,13 @@ runs:
           fi
         elif [[ $toolchain =~ ^stable' 'minus' '[0-9]+' 'releases?$ ]]; then
           echo "toolchain=1.$((($(date +%s)/60/60/24-16569)/7/6-${toolchain//[^0-9]/}))" >> $GITHUB_OUTPUT
+        elif [[ $toolchain =~ ^1\.[0-9]+$ ]]; then
+          echo "toolchain=1.$((i=${toolchain#1.}, c=($(date +%s)/60/60/24-16569)/7/6, i+9*i*(10*i<=c)+90*i*(100*i<=c)))" >> $GITHUB_OUTPUT
         else
           echo "toolchain=$toolchain" >> $GITHUB_OUTPUT
         fi
       env:
-        toolchain: ${{inputs.toolchain}}
+        toolchain: 1.65.0
       shell: bash
 
     - id: flags