diff --git a/Gemfile b/Gemfile
index 3ed7947..acff08d 100644
--- a/Gemfile
+++ b/Gemfile
@@ -12,6 +12,7 @@ gem 'puma', '~> 3.0'
 gem 'jsonapi_suite', '~> 0.5'
 gem 'jsonapi-rails', '~> 0.1'
 gem 'kaminari', '~> 0.17'
+gem 'numbers_in_words'
 
 group :development, :test do
   gem 'pry'
diff --git a/Gemfile.lock b/Gemfile.lock
index 6a4e11d..b30ff97 100644
--- a/Gemfile.lock
+++ b/Gemfile.lock
@@ -102,6 +102,8 @@ GEM
     nio4r (2.0.0)
     nokogiri (1.7.1)
       mini_portile2 (~> 2.1.0)
+    numbers_in_words (0.4.0)
+      activesupport
     pg (0.20.0)
     pry (0.10.4)
       coderay (~> 1.1.0)
@@ -195,6 +197,7 @@ DEPENDENCIES
   jsonapi_suite (~> 0.5)
   kaminari (~> 0.17)
   listen (~> 3.0.5)
+  numbers_in_words
   pg
   pry
   pry-byebug
diff --git a/app/serializers/serializable_employee.rb b/app/serializers/serializable_employee.rb
index a3b34c0..e000f50 100644
--- a/app/serializers/serializable_employee.rb
+++ b/app/serializers/serializable_employee.rb
@@ -3,7 +3,9 @@ class SerializableEmployee < JSONAPI::Serializable::Resource
 
   attribute :first_name
   attribute :last_name
-  attribute :age
+  attribute :age do
+    NumbersInWords.in_words(@object.age)
+  end
   attribute :created_at
   attribute :updated_at
 end
diff --git a/spec/payloads/employee.rb b/spec/payloads/employee.rb
index 6de39fa..c753dd2 100644
--- a/spec/payloads/employee.rb
+++ b/spec/payloads/employee.rb
@@ -1,7 +1,7 @@
 JsonapiSpecHelpers::Payload.register(:employee) do
   key(:first_name, String)
   key(:last_name, String)
-  key(:age, Integer)
+  key(:age, String) { |r| NumbersInWords.in_words(r.age) }
 
   timestamps!
 end