diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 567a066..23513fd 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -20,23 +20,66 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-22.04, ubuntu-20.04, macos-12, macos-11, windows-2022, windows-2019]
-        compiler: [gcc]
-        version: [12, 11, 10, 9, 8, 7, 6, 5]
+        toolchain:
+          - {compiler: gcc, version: 12}
+          - {compiler: gcc, version: 11}
+          - {compiler: gcc, version: 10}
+          - {compiler: gcc, version:  9}
+          - {compiler: gcc, version:  8}
+          - {compiler: gcc, version:  7}
+          - {compiler: gcc, version:  6}
+          # {compiler: gcc, version:  5}
+        include:
+          - {os: ubuntu-22.04, toolchain: {compiler: intel, version: '2023.1'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel, version: '2023.0'}}
+          - {os: ubuntu-22.04, toolchain: {compiler: intel, version: '2022.2.1'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel, version: '2022.2'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel, version: '2022.1'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel, version: '2022.0'}}
+          - {os: ubuntu-22.04, toolchain: {compiler: intel, version: '2021.4'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel, version: '2021.3'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel, version: '2021.2'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel, version: '2021.1.2'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel, version: '2021.1'}}
+
+          - {os: ubuntu-22.04, toolchain: {compiler: intel-classic, version: '2021.9'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel-classic, version: '2021.8'}}
+          - {os: ubuntu-22.04, toolchain: {compiler: intel-classic, version: '2021.7.1'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel-classic, version: '2021.7'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel-classic, version: '2021.6'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel-classic, version: '2021.5'}}
+          - {os: ubuntu-22.04, toolchain: {compiler: intel-classic, version: '2021.4'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel-classic, version: '2021.3'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel-classic, version: '2021.2'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel-classic, version: '2021.1.2'}}
+          # {os: ubuntu-22.04, toolchain: {compiler: intel-classic, version: '2021.1'}}
+
+          - {os: macos-12, toolchain: {compiler: intel-classic, version: '2021.9'}}
+          # {os: macos-12, toolchain: {compiler: intel-classic, version: '2021.8'}}
+          - {os: macos-12, toolchain: {compiler: intel-classic, version: '2021.7.1'}}
+          # {os: macos-12, toolchain: {compiler: intel-classic, version: '2021.7'}}
+          # {os: macos-12, toolchain: {compiler: intel-classic, version: '2021.6'}}
+          # {os: macos-12, toolchain: {compiler: intel-classic, version: '2021.5'}}
+          - {os: macos-12, toolchain: {compiler: intel-classic, version: '2021.4'}}
+          # {os: macos-12, toolchain: {compiler: intel-classic, version: '2021.3'}}
+          # {os: macos-12, toolchain: {compiler: intel-classic, version: '2021.2'}}
+          # {os: macos-12, toolchain: {compiler: intel-classic, version: '2021.1'}}
+
     steps:
 
       - name: Checkout repository
         uses: actions/checkout@v3
 
       - name: Setup Fortran
-        continue-on-error: true
+        continue-on-error: ${{ matrix.toolchain.compiler == 'gcc' }}
         id: setup-fortran
         uses: ./
         with:
-          compiler: ${{ matrix.compiler }}
-          version: ${{ matrix.version }}
+          compiler: ${{ matrix.toolchain.compiler }}
+          version: ${{ matrix.toolchain.version }}
 
       - name: Check compiler version
-        if: steps.setup-fortran.outcome == 'success'
+        if: ${{ steps.setup-fortran.outcome == 'success' }}
         shell: bash
         env:
           FC: ${{ steps.setup-fortran.outputs.fc }}
@@ -48,14 +91,14 @@ jobs:
           echo $fcv
           echo $ccv
           
-          fcv=$(echo "${fcv##*)}" | xargs)
-          ccv=$(echo "${ccv##*)}" | xargs)
+          fcv=$(echo "$fcv" | grep -woE '[0123456789.]+' | head -n 1)
+          ccv=$(echo "$ccv" | grep -woE '[0123456789.]+' | head -n 1)
           
-          [[ $fcv == ${{ matrix.version }}* ]] || (echo "unexpected Fortran compiler version: $fcv"; exit 1)
-          [[ $ccv == ${{ matrix.version }}* ]] || (echo "unexpected C compiler version: $ccv"; exit 1)
+          [[ $fcv == ${{ matrix.toolchain.version }}* ]] || (echo "unexpected Fortran compiler version: $fcv"; exit 1)
+          [[ $ccv == ${{ matrix.toolchain.version }}* ]] || (echo "unexpected C compiler version: $ccv"; exit 1)
 
       - name: Test compile program (bash)
-        if: steps.setup-fortran.outcome == 'success'
+        if: ${{ steps.setup-fortran.outcome == 'success' }}
         shell: bash
         env:
           FC: ${{ steps.setup-fortran.outputs.fc }}
@@ -66,7 +109,7 @@ jobs:
           [[ "$output" == *"hello world"* ]] && echo "$output" || (echo "Unexpected output: $output"; exit 1)
 
       - name: Test compile program (Powershell Core)
-        if: steps.setup-fortran.outcome == 'success' && runner.os == 'Windows'
+        if: ${{ steps.setup-fortran.outcome == 'success' && runner.os == 'Windows' }}
         shell: pwsh
         env:
           FC: ${{ steps.setup-fortran.outputs.fc }}
@@ -83,7 +126,7 @@ jobs:
           }
       
       - name: Test compile program (Powershell Desktop)
-        if: steps.setup-fortran.outcome == 'success' && runner.os == 'Windows'
+        if: ${{ steps.setup-fortran.outcome == 'success' && runner.os == 'Windows' }}
         shell: powershell
         env:
           FC: ${{ steps.setup-fortran.outputs.fc }}
@@ -100,7 +143,7 @@ jobs:
           }
 
       - name: Test compile program (cmd)
-        if: steps.setup-fortran.outcome == 'success' && runner.os == 'Windows'
+        if: ${{ steps.setup-fortran.outcome == 'success' && runner.os == 'Windows' }}
         shell: cmd
         env:
           FC: ${{ steps.setup-fortran.outputs.fc }}
@@ -126,10 +169,11 @@ jobs:
           fi
           
           mkdir compat
-          prefix="${{ matrix.os }},${{ matrix.compiler }},${{ matrix.version }}"
+          prefix="${{ matrix.os }},${{ matrix.toolchain.compiler }},${{ matrix.toolchain.version }}"
           echo "$prefix,$support" >> "compat/${prefix//,/_}.csv"
 
       - name: Upload compatibility report
+        if: ${{ matrix.toolchain.compiler == 'gcc' }}
         uses: actions/upload-artifact@v3
         with:
           name: compat
@@ -206,7 +250,7 @@ jobs:
           fi
 
       - name: Update README
-        if: steps.diff.outputs.diff == 'true' && github.event_name == 'push'
+        if: ${{ steps.diff.outputs.diff == 'true' && github.event_name == 'push' }}
         shell: python
         run: |
           import re
@@ -220,12 +264,12 @@ jobs:
             readme_path.open('w').write(r.sub(chunk, readme))
 
       - name: Print README diff
-        if: steps.diff.outputs.diff == 'true' && github.event_name == 'push'
+        if: ${{ steps.diff.outputs.diff == 'true' && github.event_name == 'push' }}
         run: |
           git diff README.md
 
       - name: Create pull request
-        if: steps.diff.outputs.diff == 'true' && github.event_name == 'push'
+        if: ${{ steps.diff.outputs.diff == 'true' && github.event_name == 'push' }}
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         run: |
diff --git a/README.md b/README.md
index 302db9a..20c6c37 100644
--- a/README.md
+++ b/README.md
@@ -29,24 +29,39 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
+        toolchain:
+          - {compiler: gcc, version: 11}
+          - {compiler: intel-classic, version: '2021.9'}
+        include:
+          - os: ubuntu-latest
+            toolchain: {compiler: intel, version: '2023.1'}
+        exclude:
+          - os: windows-latest
+            toolchain: {compiler: intel-classic, version: '2021.9'}
 
     steps:
-    - uses: awvwgk/setup-fortran@main
-      id: setup-fortran
-      with:
-        compiler: gcc
-        version: 11
-
-    - run: ${{ env.FC }} --version
-      env:
-        FC: ${{ steps.setup-fortran.outputs.fc }}
+      - uses: awvwgk/setup-fortran@v1
+        id: setup-fortran
+        with:
+          compiler: ${{ matrix.toolchain.compiler }}
+          version: ${{ matrix.toolchain.version }}
+
+      - run: ${{ env.FC }} --version
+        env:
+          FC: ${{ steps.setup-fortran.outputs.fc }}
 ```
 
 
 ## Options
 
-- *compiler*: Compiler toolchain to setup, available options are *gcc*
-- *version*: Version of the compiler toolchain, available options for *gcc* are *5-12*
+- *compiler*: Compiler toolchain to setup, available options are
+  - *gcc* (for `gfortran`)
+  - *intel* (for `ifx`)
+  - *intel-classic* (for `ifort`)
+- *version*: Version of the compiler toolchain, available options are
+  - *5–12* for *gcc*
+  - *2021.1–2023.1* for *intel*
+  - *2021.1–2021.9* for *intel-classic*
 
 
 ## Outputs
@@ -83,6 +98,15 @@ Support for the GCC toolchain varies across GitHub-hosted runner images.
 <!-- compat ends -->
 
 
+Supported Intel toolchains:
+
+| runner    | compiler       | version |
+| :-------- | :------------- | :------ |
+| ubuntu-\* | intel          | 2023.1, 2023.0, <br/> 2022.2.1, 2022.2, 2022.1, 2022.0, <br/> 2021.4, 2021.3, 2021.2, 2021.1.2, 2021.1 |
+| ubuntu-\* | intel-classic  | 2021.9, 2021.8, <br/> 2021.7.1, 2021.7, 2021.6, 2021.5, <br/> 2021.4, 2021.3, 2021.2, 2021.1.2, 2021.1 |
+| macos-\*  | intel-classic  | 2021.9, 2021.8, <br/> 2021.7.1, 2021.7, 2021.6, 2021.5, <br/> 2021.4, 2021.3, 2021.2, 2021.1 |
+
+
 ## License
 
 Licensed under the Apache License, Version 2.0 (the “License”);
diff --git a/action.yml b/action.yml
index c8e1d9b..9605ce1 100644
--- a/action.yml
+++ b/action.yml
@@ -34,30 +34,17 @@ runs:
         case $compiler in
           gcc)
             version=${VERSION:-11}
+            install_gcc $platform
             ;;
-          *)
-            exit 1
-            ;;
-        esac
-
-        case $platform in
-          linux*)
-            install_gcc_apt
-            ;;
-          darwin*)
-            install_gcc_brew
-            ;;
-          mingw*)
-            install_gcc_choco
-            ;;
-          msys*)
-            install_gcc_choco
+          intel-classic)
+            version=${VERSION:-2023.1.0}
+            install_intel $platform true
             ;;
-          cygwin*)
-            install_gcc_choco
+          intel)
+            version=${VERSION:-2023.1.0}
+            install_intel $platform false
             ;;
           *)
-            echo "Unsupported platform: $platform"
             exit 1
             ;;
         esac
diff --git a/setup-fortran.sh b/setup-fortran.sh
index 1378933..3a59907 100755
--- a/setup-fortran.sh
+++ b/setup-fortran.sh
@@ -2,6 +2,19 @@
 
 set -ex
 
+require_fetch()
+{
+  if command -v curl > /dev/null 2>&1; then
+    fetch="curl -L"
+  elif command -v wget > /dev/null 2>&1; then
+    fetch="wget -O -"
+  else
+    echo "No download mechanism found. Install curl or wget first."
+    exit 1
+  fi
+}
+
+
 install_gcc_brew()
 {
   brew install gcc@${version}
@@ -109,15 +122,7 @@ install_gcc_winlibs()
       ;;
   esac
 
-  if command -v curl > /dev/null 2>&1; then
-    fetch="curl -L"
-  elif command -v wget > /dev/null 2>&1; then
-    fetch="wget -O -"
-  else
-    echo "No download mechanism found. Install curl or wget first."
-    exit 1
-  fi
-
+  require_fetch
   $fetch "$repo/$tag/$zip" > gcc.zip
 
   unzip -qo gcc.zip "mingw64/bin/*" -d /
@@ -126,3 +131,253 @@ install_gcc_winlibs()
   export CC="gcc"
   export CXX="g++"
 }
+
+install_gcc()
+{
+  local platform=$1
+  case $platform in
+    linux*)
+      install_gcc_apt
+      ;;
+    darwin*)
+      install_gcc_brew
+      ;;
+    mingw*)
+      install_gcc_choco
+      ;;
+    msys*)
+      install_gcc_choco
+      ;;
+    cygwin*)
+      install_gcc_choco
+      ;;
+    *)
+      echo "Unsupported platform: $platform"
+      exit 1
+      ;;
+  esac
+}
+
+export_intel_vars()
+{
+  cat >> $GITHUB_ENV <<EOF
+LD_LIBRARY_PATH=$LD_LIBRARY_PATH
+LIBRARY_PATH=$LIBRARY_PATH
+INFOPATH=$INFOPATH
+MANPATH=$MANPATH
+ONEAPI_ROOT=$ONEAPI_ROOT
+CLASSPATH=$CLASSPATH
+CMAKE_PREFIX_PATH=$CMAKE_PREFIX_PATH
+OCL_ICD_FILENAMES=$OCL_ICD_FILENAMES
+INTEL_PYTHONHOME=$INTEL_PYTHONHOME
+CPATH=$CPATH
+EOF
+  for path in ${PATH//:/ }; do
+    echo $path >> $GITHUB_PATH
+  done
+}
+
+intel_version_map_l()
+{
+  local actual_version=$1
+  local classic=$2
+  if $classic; then
+    case $actual_version in
+      2021.9.0 | 2021.9)
+        version=2023.1.0
+        ;;
+      2021.8.0 | 2021.8)
+        version=2023.0.0
+        ;;
+      2021.7.1)
+        version=2022.2.1
+        ;;
+      2021.7.0 | 2021.7)
+        version=2022.2.0
+        ;;
+      2021.6.0 | 2021.6)
+        version=2022.1.0
+        ;;
+      2021.5.0 | 2021.5)
+        version=2022.0.2
+        # version=2022.0.1
+        ;;
+      2021.4 | 2021.3 | 2021.2)
+        version=$actual_version.0
+        ;;
+      2021.1)
+        version=2021.1.1
+        ;;
+      *)
+        version=$actual_version
+        ;;
+    esac
+  else
+    case $actual_version in
+      2022.0.0 | 2022.0)
+        version=2022.0.2
+        ;;
+      2023.1 | 2023.0 | 2022.2 | 2022.1 | 2021.4 | 2021.3 | 2021.2)
+        version=$actual_version.0
+        ;;
+      2021.1)
+        version=2021.1.1
+        ;;
+      *)
+        version=$actual_version
+        ;;
+    esac
+  fi
+}
+
+intel_version_map_m()
+{
+  local actual_version=$1
+  case $actual_version in
+    2021.9.0 | 2021.9)
+      version=2023.1.0
+      ;;
+    2021.8.0 | 2021.8)
+      version=2023.0.0
+      ;;
+    2021.7.1)
+      version=2022.3.1
+      ;;
+    2021.7.0 | 2021.7)
+      version=2022.3.0
+      ;;
+    2021.6.0 | 2021.6)
+      version=2022.2.0
+      ;;
+    2021.5.0 | 2021.5)
+      version=2022.1.0
+      ;;
+    2021.4 | 2021.3 | 2021.2 | 2021.1)
+      version=$actual_version.0
+      ;;
+    *)
+      version=$actual_version
+      ;;
+  esac
+}
+
+install_intel_apt()
+{
+  local version=$1
+  local classic=$2
+  intel_version_map_l $version $classic
+
+  require_fetch
+  local _KEY="GPG-PUB-KEY-INTEL-SW-PRODUCTS-2023.PUB"
+  $fetch https://apt.repos.intel.com/intel-gpg-keys/$_KEY > $_KEY
+  sudo apt-key add $_KEY
+  rm $_KEY
+  unset $_KEY
+  echo "deb https://apt.repos.intel.com/oneapi all main" \
+    | sudo tee /etc/apt/sources.list.d/oneAPI.list
+  sudo apt-get update
+
+  sudo apt-get install \
+    intel-oneapi-compiler-{fortran,dpcpp-cpp-and-cpp-classic}-$version
+
+  source /opt/intel/oneapi/setvars.sh
+  export_intel_vars
+
+  if $classic; then
+    export FC="ifort"
+    export CC="icc"
+    export CXX="icpc"
+  else
+    export FC="ifx"
+    export CC="icx"
+    export CXX="icpx"
+  fi
+}
+
+install_intel_dmg()
+{
+  local version=$1
+  intel_version_map_m $version
+
+  case $version in
+    2021.1.0)
+      MACOS_BASEKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/17426/m_BaseKit_p_2021.1.0.2427.dmg
+      MACOS_HPCKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/17398/m_HPCKit_p_2021.1.0.2681.dmg
+      ;;
+    2021.2.0)
+      MACOS_BASEKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/17714/m_BaseKit_p_2021.2.0.2855.dmg
+      MACOS_HPCKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/17643/m_HPCKit_p_2021.2.0.2903.dmg
+      ;;
+    2021.3.0)
+      MACOS_BASEKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/17969/m_BaseKit_p_2021.3.0.3043.dmg
+      MACOS_HPCKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/17890/m_HPCKit_p_2021.3.0.3226.dmg
+      ;;
+    2021.4.0)
+      MACOS_BASEKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/18256/m_BaseKit_p_2021.4.0.3384.dmg
+      MACOS_HPCKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/18242/m_HPCKit_p_2021.4.0.3389.dmg
+      ;;
+    2022.1.0)
+      MACOS_BASEKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/18342/m_BaseKit_p_2022.1.0.92.dmg
+      MACOS_HPCKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/18341/m_HPCKit_p_2022.1.0.86.dmg
+      ;;
+    2022.2.0)
+      MACOS_BASEKIT_URL=https://registrationcenter-download.intel.com/akdlm/IRC_NAS/18675/m_BaseKit_p_2022.2.0.226_offline.dmg
+      MACOS_HPCKIT_URL=https://registrationcenter-download.intel.com/akdlm/IRC_NAS/18681/m_HPCKit_p_2022.2.0.158_offline.dmg
+      ;;
+    2022.3.0)
+      MACOS_BASEKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/18865/m_BaseKit_p_2022.3.0.8743.dmg
+      MACOS_HPCKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/18866/m_HPCKit_p_2022.3.0.8685.dmg
+      ;;
+    2022.3.1)
+      MACOS_BASEKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/18971/m_BaseKit_p_2022.3.1.17244.dmg
+      MACOS_HPCKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/18977/m_HPCKit_p_2022.3.1.15344.dmg
+      ;;
+    2023.0.0)
+      MACOS_BASEKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/19080/m_BaseKit_p_2023.0.0.25441.dmg
+      MACOS_HPCKIT_URL=https://registrationcenter-download.intel.com/akdlm/irc_nas/19086/m_HPCKit_p_2023.0.0.25440.dmg
+      ;;
+    2023.1.0)
+      MACOS_BASEKIT_URL=https:/registrationcenter-download.intel.com/akdlm/IRC_NAS/2516a0a0-de4d-4f3d-9e83-545b32127dbb/m_BaseKit_p_2023.1.0.45568.dmg
+      MACOS_HPCKIT_URL=https:/registrationcenter-download.intel.com/akdlm/IRC_NAS/a99cb1c5-5af6-4824-9811-ae172d24e594/m_HPCKit_p_2023.1.0.44543.dmg
+      ;;
+    *)
+      exit 1
+      ;;
+  esac
+
+  require_fetch
+  $fetch $MACOS_HPCKIT_URL > m_HPCKit.dmg
+  hdiutil attach m_HPCKit.dmg
+  sudo /Volumes/"$(basename "$MACOS_HPCKIT_URL" .dmg)"/bootstrapper.app/Contents/MacOS/bootstrapper -s \
+    --action install \
+    --eula=accept \
+    --continue-with-optional-error=yes \
+    --log-dir=.
+  hdiutil detach /Volumes/"$(basename "$MACOS_HPCKIT_URL" .dmg)" -quiet
+  rm m_HPCKit.dmg
+
+  source /opt/intel/oneapi/setvars.sh
+  export_intel_vars
+
+  export FC="ifort"
+  export CC="icc"
+  export CXX="icpc"
+}
+
+install_intel()
+{
+  local platform=$1
+  local classic=$2
+  case $platform in
+    linux*)
+      install_intel_apt $version $classic
+      ;;
+    darwin*)
+      install_intel_dmg $version
+      ;;
+    *)
+      echo "Unsupported platform: $platform"
+      exit 1
+      ;;
+  esac
+}