diff --git a/app/graphql/types/request_password_recovery_input.rb b/app/graphql/types/request_password_recovery_input.rb
index 822183e..08b8246 100644
--- a/app/graphql/types/request_password_recovery_input.rb
+++ b/app/graphql/types/request_password_recovery_input.rb
@@ -1,5 +1,5 @@
 module Types
   class RequestPasswordRecoveryInput < Types::BaseInputObject
-    argument :email, String, required: true
+    argument :email, SquishedString, required: true
   end
 end
diff --git a/app/graphql/types/sign_in_input.rb b/app/graphql/types/sign_in_input.rb
index 2bdcdc2..d066f8f 100644
--- a/app/graphql/types/sign_in_input.rb
+++ b/app/graphql/types/sign_in_input.rb
@@ -1,6 +1,6 @@
 module Types
   class SignInInput < Types::BaseInputObject
-    argument :email, String, required: true
+    argument :email, SquishedString, required: true
     argument :password, String, required: true
   end
 end
diff --git a/app/graphql/types/sign_up_input.rb b/app/graphql/types/sign_up_input.rb
index ebe512d..26168e2 100644
--- a/app/graphql/types/sign_up_input.rb
+++ b/app/graphql/types/sign_up_input.rb
@@ -1,10 +1,10 @@
 module Types
   class SignUpInput < Types::BaseInputObject
-    argument :email, String, required: true
+    argument :email, SquishedString, required: true
     argument :password, String, required: true
 
-    argument :first_name, String, required: false
-    argument :last_name, String, required: false
+    argument :first_name, SquishedString, required: false
+    argument :last_name, SquishedString, required: false
 
     argument :avatar, Types::ImageUploaderType, required: false
   end
diff --git a/app/graphql/types/squished_string.rb b/app/graphql/types/squished_string.rb
new file mode 100644
index 0000000..061a676
--- /dev/null
+++ b/app/graphql/types/squished_string.rb
@@ -0,0 +1,14 @@
+module Types
+  class SquishedString < BaseScalar
+    def self.coerce_input(input_value, _context)
+      squished = input_value.try(:squish)
+      raise GraphQL::CoercionError, "#{input_value.inspect} is not a valid string" unless squished.is_a? String
+
+      squished
+    end
+
+    def self.coerce_result(ruby_value, _context)
+      ruby_value.to_s
+    end
+  end
+end
diff --git a/app/graphql/types/update_user_input.rb b/app/graphql/types/update_user_input.rb
index 977f932..8a11753 100644
--- a/app/graphql/types/update_user_input.rb
+++ b/app/graphql/types/update_user_input.rb
@@ -1,8 +1,8 @@
 module Types
   class UpdateUserInput < Types::BaseInputObject
-    argument :email, String, required: false
-    argument :first_name, String, required: false
-    argument :last_name, String, required: false
+    argument :email, SquishedString, required: false
+    argument :first_name, SquishedString, required: false
+    argument :last_name, SquishedString, required: false
     argument :current_password, String, required: false
     argument :password, String, required: false
     argument :avatar, Types::ImageUploaderType, required: false
diff --git a/spec/graphql/types/squished_string_spec.rb b/spec/graphql/types/squished_string_spec.rb
new file mode 100644
index 0000000..51e2bf7
--- /dev/null
+++ b/spec/graphql/types/squished_string_spec.rb
@@ -0,0 +1,27 @@
+require "rails_helper"
+
+describe Types::SquishedString do
+  describe "#coerce_input" do
+    subject(:method) { described_class.coerce_input(input_value, {}) }
+
+    context "with regular string" do
+      let(:input_value) { "String without extra whitespaces" }
+
+      it { is_expected.to eq("String without extra whitespaces") }
+    end
+
+    context "with overspaced string" do
+      let(:input_value) { "  String  with \t  extra \n whitespaces  " }
+
+      it { is_expected.to eq("String with extra whitespaces") }
+    end
+
+    context "with not string provided" do
+      let(:input_value) { 42 }
+
+      it "raises graphql error" do
+        expect { method }.to raise_error(::GraphQL::CoercionError, "42 is not a valid string")
+      end
+    end
+  end
+end