diff --git a/meson.build b/meson.build
index efd0bd3319..8f8a258064 100644
--- a/meson.build
+++ b/meson.build
@@ -694,7 +694,6 @@ endif
 libgit_c_args = [
   '-DBINDIR="' + get_option('bindir') + '"',
   '-DDEFAULT_GIT_TEMPLATE_DIR="' + get_option('datadir') / 'git-core/templates' + '"',
-  '-DDEFAULT_HELP_FORMAT="' + get_option('default_help_format') + '"',
   '-DETC_GITATTRIBUTES="' + get_option('gitattributes') + '"',
   '-DETC_GITCONFIG="' + get_option('gitconfig') + '"',
   '-DFALLBACK_RUNTIME_PREFIX="' + get_option('prefix') + '"',
@@ -717,6 +716,18 @@ if pager_opt != '' and pager_opt != 'less'
   libgit_c_args += '-DDEFAULT_PAGER="' + pager_opt + '"'
 endif
 
+help_format_opt = get_option('default_help_format')
+if help_format_opt == 'platform'
+  if host_machine.system() == 'windows'
+    help_format_opt = 'html'
+  else
+    help_format_opt = 'man'
+  endif
+endif
+if help_format_opt != 'man'
+    libgit_c_args += '-DDEFAULT_HELP_FORMAT="' + help_format_opt + '"'
+endif
+
 libgit_include_directories = [ '.' ]
 libgit_dependencies = [ ]
 
diff --git a/meson_options.txt b/meson_options.txt
index 78d172a740..8ac30a5223 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -95,7 +95,7 @@ option('highlight_bin', type: 'string', value: 'highlight')
 # Documentation.
 option('docs', type: 'array', choices: ['man', 'html'], value: [],
   description: 'Which documenattion formats to build and install.')
-option('default_help_format', type: 'combo', choices: ['man', 'html'], value: 'man',
+option('default_help_format', type: 'combo', choices: ['man', 'html', 'platform'], value: 'platform',
   description: 'Default format used when executing git-help(1).')
 option('docs_backend', type: 'combo', choices: ['asciidoc', 'asciidoctor', 'auto'], value: 'auto',
   description: 'Which backend to use to generate documentation.')