diff --git a/README.md b/README.md
index 3385e5d..afa53a7 100644
--- a/README.md
+++ b/README.md
@@ -16,20 +16,21 @@ If you don’t use Homebrew you can also install directly from source. Clone the
 ## Usage
 
 ```
-USAGE: make-colors <input> [--ios] [--android] [--html] [--prefix <prefix>] [--output <output>]
+USAGE: make-colors <input> [--ios] [--android] [--html] [--prefix <prefix>] [--output <output>] [--dump]
 
 ARGUMENTS:
   <input>                 The color list to process. 
         Use - to process the standard input.
 
 OPTIONS:
-  --ios/--android/--html  The formatter to use (default: ios)
-  --prefix <prefix>       Prefix for color names 
+  --ios/--android/--html  The formatter to use. (default: ios)
+  --prefix <prefix>       Prefix for color names. 
   --output <output>       Output file to write. 
         Use - for standard output.
         Default is the input file name with the appropriate file extension. If
-        the input is read from the standard input the default is standard
-        output.
+        the input is - the default is standard output.
+        Note that asset catalogs cannot be written to standard output.
+  --dump                  List read colors on console. 
   -h, --help              Show help information.
 ```
 
diff --git a/Sources/LibMakeColors/MakeColors.swift b/Sources/LibMakeColors/MakeColors.swift
index 3140601..a2db649 100644
--- a/Sources/LibMakeColors/MakeColors.swift
+++ b/Sources/LibMakeColors/MakeColors.swift
@@ -60,6 +60,9 @@ public final class MakeColors: ParsableCommand, Context {
     @Option(help: HelpTexts.output)
     var output: String?
 
+    @Flag(help: "List read colors on console.")
+    var dump = false
+
     public init() {}
 
     public func run() throws {
@@ -68,19 +71,8 @@ public final class MakeColors: ParsableCommand, Context {
 
         let data = try scanner.colorList()
 
-        for (key, color) in data.sorted() {
-            let resolved = try data.resolve(key)
-            switch color {
-            case .color:
-                print(key.insertCamelCaseSeparators(), resolved, separator: ": ")
-
-            case let .reference(referenced):
-                print(
-                    "\(key.insertCamelCaseSeparators()) (@\(referenced.insertCamelCaseSeparators()))",
-                    resolved,
-                    separator: ": "
-                )
-            }
+        if dump {
+            try dump(data: data)
         }
 
         let generator = formatter.type.init(context: self)
@@ -109,6 +101,23 @@ public final class MakeColors: ParsableCommand, Context {
         return input
     }
 
+    func dump(data: [String: ColorDef]) throws {
+        for (key, color) in data.sorted() {
+            let resolved = try data.resolve(key)
+            switch color {
+            case .color:
+                print(key.insertCamelCaseSeparators(), resolved, separator: ": ")
+
+            case let .reference(referenced):
+                print(
+                    "\(key.insertCamelCaseSeparators()) (@\(referenced.insertCamelCaseSeparators()))",
+                    resolved,
+                    separator: ": "
+                )
+            }
+        }
+    }
+
     func writeOutput(_ wrapper: FileWrapper) throws {
         if shouldWriteToStdout {
             guard wrapper.isRegularFile, let contents = wrapper.regularFileContents else {