diff --git a/Gemfile.lock b/Gemfile.lock
index f07aaf2..b919a71 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -15,7 +15,7 @@ GEM
     ffi (1.10.0)
     minitest (5.11.3)
     ox (2.10.0)
-    rake (12.3.0)
+    rake (13.0.1)
     rspec (3.8.0)
       rspec-core (~> 3.8.0)
       rspec-expectations (~> 3.8.0)
@@ -38,7 +38,7 @@ PLATFORMS
 
 DEPENDENCIES
   excel_to_code!
-  rake (~> 12)
+  rake (~> 13)
 
 BUNDLED WITH
    1.17.1
diff --git a/excel_to_code.gemspec b/excel_to_code.gemspec
index 0f989ef..8d42539 100644
--- a/excel_to_code.gemspec
+++ b/excel_to_code.gemspec
@@ -9,7 +9,7 @@ Gem::Specification.new do |s|
   s.add_runtime_dependency 'ffi', '~> 1.9', '>= 1.9.18'
   s.add_runtime_dependency 'ox', '~> 2.8', '>= 2.8.2'
   s.add_runtime_dependency 'minitest', '~> 5.11', '>= 5.11.1'
-  s.add_development_dependency 'rake', '~> 12'
+  s.add_development_dependency 'rake', '~> 13'
   s.required_ruby_version = ">= 2.3.0"
   s.author = "Thomas Counsell, Green on Black Ltd"
   s.email = "tamc@greenonblack.com"