diff --git a/README.md b/README.md
index fec8350ef..8d1d28877 100644
--- a/README.md
+++ b/README.md
@@ -152,7 +152,7 @@ Debugging
 
 Misc
   edit           Open a file or source location.
-  measure        `measure` enables the mode to measure processing time. `measure :off` disables it.
+  measure        `measure` enables the mode to measure processing time. `measure off` disables it.
 
 Context
   show_doc       Look up documentation with RI.
diff --git a/lib/irb/command/measure.rb b/lib/irb/command/measure.rb
index f96be20de..5f72ab72a 100644
--- a/lib/irb/command/measure.rb
+++ b/lib/irb/command/measure.rb
@@ -3,42 +3,51 @@ module IRB
 
   module Command
     class Measure < Base
-      include RubyArgsExtractor
-
       category "Misc"
-      description "`measure` enables the mode to measure processing time. `measure :off` disables it."
-
-      def initialize(*args)
-        super(*args)
-      end
+      description "`measure` enables the mode to measure processing time. `measure off` disables it."
 
       def execute(arg)
         if arg&.match?(/^do$|^do[^\w]|^\{/)
           warn 'Configure IRB.conf[:MEASURE_PROC] to add custom measure methods.'
           return
         end
-        args, kwargs = ruby_args(arg)
-        execute_internal(*args, **kwargs)
+
+        if arg.empty?
+          execute_internal(nil, nil)
+        elsif arg.start_with? ':'
+          # Legacy style `measure :stackprof`, `measure :off, :time`
+          type, arg_val = arg.split(/,\s*/, 2).map { |v| v.sub(/\A:/, '') }
+          warn "`measure #{arg}` is deprecated. Please use `measure #{[type, arg_val].compact.join(' ')}` instead."
+          execute_internal(type.to_sym, arg_val)
+        else
+          type, arg_val = arg.split(/\s+/, 2)
+          execute_internal(type.to_sym, arg_val)
+        end
       end
 
-      def execute_internal(type = nil, arg = nil)
+      def execute_internal(type, arg)
         # Please check IRB.init_config in lib/irb/init.rb that sets
         # IRB.conf[:MEASURE_PROC] to register default "measure" methods,
-        # "measure :time" (abbreviated as "measure") and "measure :stackprof".
+        # "measure time" (abbreviated as "measure") and "measure stackprof".
 
         case type
         when :off
-          IRB.unset_measure_callback(arg)
+          IRB.unset_measure_callback(arg&.to_sym)
         when :list
           IRB.conf[:MEASURE_CALLBACKS].each do |type_name, _, arg_val|
             puts "- #{type_name}" + (arg_val ? "(#{arg_val.inspect})" : '')
           end
-        when :on
-          added = IRB.set_measure_callback(arg)
-          puts "#{added[0]} is added." if added
         else
-          added = IRB.set_measure_callback(type, arg)
-          puts "#{added[0]} is added." if added
+          type, arg = arg&.to_sym, nil if type == :on
+
+          measure_methods = IRB.conf[:MEASURE_PROC].keys.map(&:downcase)
+          if type && !measure_methods.include?(type)
+            puts "Measure method `#{type}` not found."
+            puts "Available measure methods: %w[#{measure_methods.join(' ')}]."
+          else
+            added = IRB.set_measure_callback(type&.to_sym, arg)
+            puts "#{added[0]} is added." if added
+          end
         end
         nil
       end
diff --git a/lib/irb/init.rb b/lib/irb/init.rb
index 7dc08912e..a13fa95c4 100644
--- a/lib/irb/init.rb
+++ b/lib/irb/init.rb
@@ -204,19 +204,9 @@ def IRB.set_measure_callback(type = nil, arg = nil, &block)
         added = [type_sym, IRB.conf[:MEASURE_PROC][type_sym], arg]
       end
     elsif IRB.conf[:MEASURE_PROC][:CUSTOM]
-      added = [:CUSTOM, IRB.conf[:MEASURE_PROC][:CUSTOM], arg]
-    elsif block_given?
-      added = [:BLOCK, block, arg]
-      found = IRB.conf[:MEASURE_CALLBACKS].find{ |m| m[0] == added[0] && m[2] == added[2] }
-      if found
-        found[1] = block
-        return added
-      else
-        IRB.conf[:MEASURE_CALLBACKS] << added
-        return added
-      end
+      added = [:CUSTOM, IRB.conf[:MEASURE_PROC][:CUSTOM], nil]
     else
-      added = [:TIME, IRB.conf[:MEASURE_PROC][:TIME], arg]
+      added = [:TIME, IRB.conf[:MEASURE_PROC][:TIME], nil]
     end
     if added
       IRB.conf[:MEASURE] = true
diff --git a/test/irb/test_command.rb b/test/irb/test_command.rb
index 567c3216c..93a8eb0bd 100644
--- a/test/irb/test_command.rb
+++ b/test/irb/test_command.rb
@@ -208,6 +208,13 @@ def test_irb_info_lang
   end
 
   class MeasureTest < CommandTestCase
+    CUSTOM_MEASURE_PROC = proc { |context, line, line_no, &block|
+      raise 'Wrong argument' unless IRB::Context === context && String === line && Integer === line_no
+      time = Time.now
+      result = block.()
+      puts 'custom processing time: %fs' % (Time.now - time) if IRB.conf[:MEASURE]
+      result
+    }
     def test_measure
       conf = {
         PROMPT: {
@@ -225,11 +232,11 @@ def test_measure
       out, err = execute_lines(
         "measure\n",
         "3\n",
-        "measure :off\n",
+        "measure off\n",
         "3\n",
-        "measure :on\n",
+        "measure on\n",
         "3\n",
-        "measure :off\n",
+        "measure off\n",
         "3\n",
         conf: conf,
         main: c
@@ -282,7 +289,7 @@ def test_measure_enabled_by_rc
 
       out, err = execute_lines(
         "3\n",
-        "measure :off\n",
+        "measure off\n",
         "3\n",
         conf: conf,
       )
@@ -292,12 +299,6 @@ def test_measure_enabled_by_rc
     end
 
     def test_measure_enabled_by_rc_with_custom
-      measuring_proc = proc { |line, line_no, &block|
-        time = Time.now
-        result = block.()
-        puts 'custom processing time: %fs' % (Time.now - time) if IRB.conf[:MEASURE]
-        result
-      }
       conf = {
         PROMPT: {
           DEFAULT: {
@@ -308,12 +309,12 @@ def test_measure_enabled_by_rc_with_custom
         },
         PROMPT_MODE: :DEFAULT,
         MEASURE: true,
-        MEASURE_PROC: { CUSTOM: measuring_proc }
+        MEASURE_PROC: { CUSTOM: CUSTOM_MEASURE_PROC }
       }
 
       out, err = execute_lines(
         "3\n",
-        "measure :off\n",
+        "measure off\n",
         "3\n",
         conf: conf,
       )
@@ -322,12 +323,6 @@ def test_measure_enabled_by_rc_with_custom
     end
 
     def test_measure_with_custom
-      measuring_proc = proc { |line, line_no, &block|
-        time = Time.now
-        result = block.()
-        puts 'custom processing time: %fs' % (Time.now - time) if IRB.conf[:MEASURE]
-        result
-      }
       conf = {
         PROMPT: {
           DEFAULT: {
@@ -338,13 +333,13 @@ def test_measure_with_custom
         },
         PROMPT_MODE: :DEFAULT,
         MEASURE: false,
-        MEASURE_PROC: { CUSTOM: measuring_proc }
+        MEASURE_PROC: { CUSTOM: CUSTOM_MEASURE_PROC }
       }
       out, err = execute_lines(
         "3\n",
         "measure\n",
         "3\n",
-        "measure :off\n",
+        "measure off\n",
         "3\n",
         conf: conf
       )
@@ -365,24 +360,24 @@ def test_measure_toggle
         PROMPT_MODE: :DEFAULT,
         MEASURE: false,
         MEASURE_PROC: {
-          FOO: proc { |&block| puts 'foo'; block.call },
-          BAR: proc { |&block| puts 'bar'; block.call }
+          FOO: proc { |ctx, line, line_no, arg, &block| puts "foo(#{arg.inspect})"; block.call },
+          BAR: proc { |ctx, line, line_no, arg, &block| puts "bar(#{arg.inspect})"; block.call }
         }
       }
       out, err = execute_lines(
-        "measure :foo\n",
+        "measure foo arg\n",
         "1\n",
-        "measure :on, :bar\n",
+        "measure on bar\n",
         "2\n",
-        "measure :off, :foo\n",
+        "measure off foo\n",
         "3\n",
-        "measure :off, :bar\n",
+        "measure off bar\n",
         "4\n",
         conf: conf
       )
 
       assert_empty err
-      assert_match(/\AFOO is added\.\nfoo\n=> 1\nBAR is added\.\nbar\nfoo\n=> 2\nbar\n=> 3\n=> 4\n/, out)
+      assert_match(/\AFOO is added\.\nfoo\("arg"\)\n=> 1\nBAR is added\.\nbar\(nil\)\nfoo\("arg"\)\n=> 2\nbar\(nil\)\n=> 3\n=> 4\n/, out)
     end
 
     def test_measure_with_proc_warning
@@ -410,6 +405,32 @@ def test_measure_with_proc_warning
       assert_match(/\A=> 3\n=> 3\n/, out)
       assert_empty(c.class_variables)
     end
+
+    def test_legacy_measure_warning
+      conf = {
+        MEASURE_PROC: {
+          FOO: proc {},
+          BAR: proc {},
+        }
+      }
+      out, err = execute_lines(
+        "measure :foo\n",
+        "measure :on, :bar\n",
+        conf: conf
+      )
+      assert_match(/FOO is added/, out)
+      assert_match(/BAR is added/, out)
+      assert_match(/`measure :foo` is deprecated. Please use `measure foo`/, err)
+      assert_match(/`measure :on, :bar` is deprecated. Please use `measure on bar`/, err)
+    end
+
+    def test_unknown_method
+      out, err = execute_lines("measure foo\n", "measure on bar\n")
+      assert_empty(err)
+      assert_match(/`foo` not found/, out)
+      assert_match(/`bar` not found/, out)
+      assert_match(/time stackprof/, out)
+    end
   end
 
   class IrbSourceTest < CommandTestCase