diff --git a/Gemfile b/Gemfile
index db23cc8..e35f3da 100644
--- a/Gemfile
+++ b/Gemfile
@@ -1,6 +1,6 @@
 source "https://rubygems.org"
 
-gem "jekyll", ">= 3.8.6", "< 5.0"
+gem "jekyll", ">= 4.0.0", "< 5.0"
 
 # plugins
 group :jekyll_plugins do
diff --git a/Gemfile.lock b/Gemfile.lock
index 89d2f1e..7bcf94e 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -97,7 +97,7 @@ PLATFORMS
 
 DEPENDENCIES
   html-proofer
-  jekyll (>= 3.8.6, < 5.0)
+  jekyll (>= 4.0.0, < 5.0)
   jekyll-archives
   jekyll-paginate
   jekyll-redirect-from