diff --git a/.ruby-version b/.ruby-version
index 0bee604..79a6144 100644
--- a/.ruby-version
+++ b/.ruby-version
@@ -1 +1 @@
-2.3.3
+2.4.4
diff --git a/.travis.yml b/.travis.yml
index d5de54a..21f6d76 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,10 +1,8 @@
 language: ruby
 cache: bundler
 rvm:
-  - 2.2.9
-  - 2.3.6
-  - 2.4.3
-  - 2.5.0
+  - 2.4.4
+  - 2.5.1
 before_install:
   - gem update --system
   - gem update bundler
diff --git a/microformats.gemspec b/microformats.gemspec
index 5d50c1a..cc0668e 100644
--- a/microformats.gemspec
+++ b/microformats.gemspec
@@ -4,7 +4,7 @@ $LOAD_PATH.unshift(lib) unless $LOAD_PATH.include?(lib)
 require 'microformats/version'
 
 Gem::Specification.new do |spec|
-  spec.required_ruby_version = ['>= 2.0', '< 2.6']
+  spec.required_ruby_version = ['>= 2.4', '< 2.6']
 
   spec.name          = 'microformats'
   spec.version       = Microformats::VERSION