diff --git a/lib/http/response/status.rb b/lib/http/response/status.rb
index b9c098f1..73fb3444 100644
--- a/lib/http/response/status.rb
+++ b/lib/http/response/status.rb
@@ -86,31 +86,31 @@ def to_s
       # Check if status code is informational (1XX)
       # @return [Boolean]
       def informational?
-        INFORMATIONAL.keys.include?(code)
+        100 <= code && code < 200
       end
 
       # Check if status code is successful (2XX)
       # @return [Boolean]
       def success?
-        SUCCESSFUL.keys.include?(code)
+        200 <= code && code < 300
       end
 
       # Check if status code is redirection (3XX)
       # @return [Boolean]
       def redirect?
-        REDIRECTION.keys.include?(code)
+        300 <= code && code < 400
       end
 
       # Check if status code is client error (4XX)
       # @return [Boolean]
       def client_error?
-        CLIENT_ERROR.keys.include?(code)
+        400 <= code && code < 500
       end
 
       # Check if status code is server error (5XX)
       # @return [Boolean]
       def server_error?
-        SERVER_ERROR.keys.include?(code)
+        500 <= code && code < 600
       end
 
       # Symbolized {#reason}
diff --git a/lib/http/response/status/reasons.rb b/lib/http/response/status/reasons.rb
index b986a886..119c53ba 100644
--- a/lib/http/response/status/reasons.rb
+++ b/lib/http/response/status/reasons.rb
@@ -13,13 +13,10 @@ class Status < ::Delegator
       #   REASONS[414] # => "Request-URI Too Long"
       #
       # @return [Hash<Fixnum => String>]
-      INFORMATIONAL = {
+      REASONS = {
         100 => "Continue",
         101 => "Switching Protocols",
-        102 => "Processing"
-      }.each { |_, v| v.freeze }.freeze
-
-      SUCCESSFUL = {
+        102 => "Processing",
         200 => "OK",
         201 => "Created",
         202 => "Accepted",
@@ -29,10 +26,7 @@ class Status < ::Delegator
         206 => "Partial Content",
         207 => "Multi-Status",
         208 => "Already Reported",
-        226 => "IM Used"
-      }.each { |_, v| v.freeze }.freeze
-
-      REDIRECTION = {
+        226 => "IM Used",
         300 => "Multiple Choices",
         301 => "Moved Permanently",
         302 => "Found",
@@ -40,10 +34,7 @@ class Status < ::Delegator
         304 => "Not Modified",
         305 => "Use Proxy",
         307 => "Temporary Redirect",
-        308 => "Permanent Redirect"
-      }.each { |_, v| v.freeze }.freeze
-
-      CLIENT_ERROR = {
+        308 => "Permanent Redirect",
         400 => "Bad Request",
         401 => "Unauthorized",
         402 => "Payment Required",
@@ -70,10 +61,7 @@ class Status < ::Delegator
         428 => "Precondition Required",
         429 => "Too Many Requests",
         431 => "Request Header Fields Too Large",
-        451 => "Unavailable For Legal Reasons"
-      }.each { |_, v| v.freeze }.freeze
-
-      SERVER_ERROR = {
+        451 => "Unavailable For Legal Reasons",
         500 => "Internal Server Error",
         501 => "Not Implemented",
         502 => "Bad Gateway",
@@ -86,14 +74,6 @@ class Status < ::Delegator
         510 => "Not Extended",
         511 => "Network Authentication Required"
       }.each { |_, v| v.freeze }.freeze
-
-      REASONS = [
-        INFORMATIONAL,
-        SUCCESSFUL,
-        REDIRECTION,
-        CLIENT_ERROR,
-        SERVER_ERROR
-      ].inject(&:merge).each { |_, v| v.freeze }.freeze
     end
   end
 end