diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -127,11 +127,11 @@
 During submission of patches, arcanist will automatically run `arc lint` to
 enforce Bitcoin ABC code formatting standards, and often suggests changes.
 If code formatting tools do not install automatically on your system, you
-will have to install clang-format-7, autopep8, flake8, phpcs and shellcheck.
+will have to install clang-format-8, autopep8, flake8, phpcs and shellcheck.
 
-To install clang-format-7 on Ubuntu (>= 18.04+updates) or Debian (>= 10):
+To install clang-format-8 on Ubuntu (>= 18.04+updates) or Debian (>= 10):
 ```
-sudo apt-get install clang-format-7
+sudo apt-get install clang-format-8
 ```
 If not available in the distribution, clang-format-7 can be installed from
 https://releases.llvm.org/download.html or https://apt.llvm.org
diff --git a/arcanist/linter/ClangFormatLinter.php b/arcanist/linter/ClangFormatLinter.php
--- a/arcanist/linter/ClangFormatLinter.php
+++ b/arcanist/linter/ClangFormatLinter.php
@@ -52,7 +52,7 @@
      * version should be >= 8.0 and < 9.0.
      */
     if ($version[0] != '8') {
-      throw new Exception(pht('Linter %s requires clang-format version 7.x. '.
+      throw new Exception(pht('Linter %s requires clang-format version 8.x. '.
                               'You have version %s.',
                               ClangFormatLinter::class,
                               $version));