diff --git a/modules/juce_graphics/colour/juce_Colour.cpp b/modules/juce_graphics/colour/juce_Colour.cpp
index b662bc1ec9..94f2c468e6 100644
--- a/modules/juce_graphics/colour/juce_Colour.cpp
+++ b/modules/juce_graphics/colour/juce_Colour.cpp
@@ -460,7 +460,7 @@ Colour Colour::withMultipliedLightness (float amount) const noexcept
 //==============================================================================
 Colour Colour::brighter (float amount) const noexcept
 {
-    jassert (0.0f <= amount && amount <= 1.0f);
+    jassert (amount >= 0.0f);
     amount = 1.0f / (1.0f + amount);
 
     return Colour ((uint8) (255 - (amount * (255 - getRed()))),
@@ -471,7 +471,7 @@ Colour Colour::brighter (float amount) const noexcept
 
 Colour Colour::darker (float amount) const noexcept
 {
-    jassert (0.0f <= amount && amount <= 1.0f);
+    jassert (amount >= 0.0f);
     amount = 1.0f / (1.0f + amount);
 
     return Colour ((uint8) (amount * getRed()),
diff --git a/modules/juce_graphics/colour/juce_Colour.h b/modules/juce_graphics/colour/juce_Colour.h
index 82e2329230..b8fb7535c8 100644
--- a/modules/juce_graphics/colour/juce_Colour.h
+++ b/modules/juce_graphics/colour/juce_Colour.h
@@ -351,15 +351,15 @@ public:
 
     //==============================================================================
     /** Returns a brighter version of this colour.
-        @param amountBrighter   how much brighter to make it - a value from 0 to 1.0 where 0 is
-                                unchanged, and higher values make it brighter
+        @param amountBrighter   how much brighter to make it - a value greater than or equal to 0,
+                                where 0 is unchanged, and higher values make it brighter
         @see withMultipliedBrightness
     */
     Colour brighter (float amountBrighter = 0.4f) const noexcept;
 
     /** Returns a darker version of this colour.
-        @param amountDarker     how much darker to make it - a value from 0 to 1.0 where 0 is
-                                unchanged, and higher values make it darker
+        @param amountDarker     how much darker to make it - a value greater than or equal to 0,
+                                where 0 is unchanged, and higher values make it darker
         @see withMultipliedBrightness
     */
     Colour darker (float amountDarker = 0.4f) const noexcept;