diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index b9ceaac69..8f754a2bc 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -43,7 +43,7 @@ concurrency:
 jobs:
 
   pretty:
-    runs-on: ubuntu-20.04
+    runs-on: ubuntu-22.04
     steps:
     - uses: actions/checkout@v3
       with:
@@ -51,7 +51,7 @@ jobs:
     - name: Bootstrap
       run: |
         sudo rm /etc/apt/sources.list.d/* && sudo apt-get update
-        sudo apt-get --no-install-recommends install -y clang-format-9 clang-tidy-9 shellcheck
+        sudo apt-get --no-install-recommends install -y clang-format-14 clang-tidy-9 shellcheck
         python3 -m pip install yapf==0.31.0
         sudo snap install shfmt
     - name: Check
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 2e99d4d45..ae564f227 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -109,7 +109,7 @@ This will open up a text editor where you can specify which commits to squash.
 
 #### Coding Conventions and Style
 
-OpenThread uses and enforces the [OpenThread Coding Conventions and Style](STYLE_GUIDE.md) on all code, except for code located in [third_party](third_party). Use `script/make-pretty` and `script/make-pretty check` to automatically reformat code and check for code-style compliance, respectively. OpenThread currently requires [clang-format v9.0.0](https://releases.llvm.org/download.html#9.0.0) for C/C++ and [yapf v0.31.0](https://github.com/google/yapf) for Python.
+OpenThread uses and enforces the [OpenThread Coding Conventions and Style](STYLE_GUIDE.md) on all code, except for code located in [third_party](third_party). Use `script/make-pretty` and `script/make-pretty check` to automatically reformat code and check for code-style compliance, respectively. OpenThread currently requires [clang-format v14.0.0](https://releases.llvm.org/download.html#14.0.0) for C/C++ and [yapf v0.31.0](https://github.com/google/yapf) for Python.
 
 As part of the cleanup process, you should also run `script/make-pretty check` to ensure that your code passes the baseline code style checks.
 
diff --git a/STYLE_GUIDE.md b/STYLE_GUIDE.md
index d8ea62496..c409c32bd 100644
--- a/STYLE_GUIDE.md
+++ b/STYLE_GUIDE.md
@@ -116,7 +116,7 @@
 
 - OpenThread uses `script/make-pretty` to reformat code and enforce code format and style. `script/make-pretty check` build target is included in OpenThread's continuous integration and must pass before a pull request is merged.
 
-- `script/make-pretty` requires [clang-format v9.0.0](https://releases.llvm.org/download.html#9.0.0) for C/C++ and [yapf v0.31.0](https://github.com/google/yapf) for Python.
+- `script/make-pretty` requires [clang-format v14.0.0](https://releases.llvm.org/download.html#14.0.0) for C/C++ and [yapf v0.31.0](https://github.com/google/yapf) for Python.
 
 ### File Names
 
diff --git a/script/bootstrap b/script/bootstrap
index cf4fff962..d25f3d2db 100755
--- a/script/bootstrap
+++ b/script/bootstrap
@@ -38,7 +38,7 @@ install_packages_pretty_format()
     echo 'Installing pretty tools useful for code contributions...'
 
     # add clang-format and clang-tidy for pretty
-    sudo apt-get --no-install-recommends install -y clang-format-9 clang-tidy-9 || echo 'WARNING: could not install clang-format-9 and clang-tidy-9, which is useful if you plan to contribute C/C++ code to the OpenThread project.'
+    sudo apt-get --no-install-recommends install -y clang-format-14 clang-tidy-9 || echo 'WARNING: could not install clang-format-14 and clang-tidy-9, which is useful if you plan to contribute C/C++ code to the OpenThread project.'
 
     # add yapf for pretty
     python3 -m pip install yapf==0.31.0 || echo 'WARNING: could not install yapf, which is useful if you plan to contribute python code to the OpenThread project.'
@@ -111,11 +111,11 @@ install_packages_brew()
     echo 'Installing pretty tools useful for code contributions...'
 
     # add clang-format for pretty
-    CLANG_FORMAT_VERSION="clang-format version 9"
-    command -v clang-format-9 || (command -v clang-format && (clang-format --version | grep -q "${CLANG_FORMAT_VERSION}")) || {
-        brew install llvm@9
-        sudo ln -s "$(brew --prefix llvm@9)/bin/clang-format" /usr/local/bin/clang-format-9
-    } || echo 'WARNING: could not install llvm@9, which is useful if you plan to contribute C/C++ code to the OpenThread project.'
+    CLANG_FORMAT_VERSION="clang-format version 14"
+    command -v clang-format-14 || (command -v clang-format && (clang-format --version | grep -q "${CLANG_FORMAT_VERSION}")) || {
+        brew install llvm@14
+        sudo ln -s "$(brew --prefix llvm@14)/bin/clang-format" /usr/local/bin/clang-format-14
+    } || echo 'WARNING: could not install llvm@14, which is useful if you plan to contribute C/C++ code to the OpenThread project.'
 
     # add yapf for pretty
     python3 -m pip install yapf || echo 'Failed to install python code formatter yapf. Install it manually if you need.'
diff --git a/script/clang-format b/script/clang-format
index 01b9535e0..1d58a925c 100755
--- a/script/clang-format
+++ b/script/clang-format
@@ -27,7 +27,7 @@
 #  POSSIBILITY OF SUCH DAMAGE.
 #
 
-CLANG_FORMAT_VERSION="clang-format version 9.0"
+CLANG_FORMAT_VERSION="clang-format version 14.0"
 
 die()
 {
@@ -39,18 +39,18 @@ die()
 # expand_aliases shell option is set using shopt.
 shopt -s expand_aliases
 
-if command -v clang-format-9 >/dev/null; then
-    alias clang-format=clang-format-9
+if command -v clang-format-14 >/dev/null; then
+    alias clang-format=clang-format-14
 elif command -v clang-format >/dev/null; then
     case "$(clang-format --version)" in
         "$CLANG_FORMAT_VERSION"*) ;;
 
         *)
-            die "$(clang-format --version); clang-format 9.0 required"
+            die "$(clang-format --version); clang-format 14.0 required"
             ;;
     esac
 else
-    die "clang-format 9.0 required"
+    die "clang-format 14.0 required"
 fi
 
 clang-format "$@" || die