diff --git a/index.js b/index.js
index d7050a6f..c13a6066 100644
--- a/index.js
+++ b/index.js
@@ -154,7 +154,8 @@ module.exports = function prettyFactory (options) {
         errorLikeKeys: errorLikeObjectKeys,
         eol: EOL,
         ident: IDENT,
-        singleLine
+        singleLine,
+        colorizer
       })
       line += prettifiedObject
     }
diff --git a/lib/colors.js b/lib/colors.js
index 0fcfb088..41018d87 100644
--- a/lib/colors.js
+++ b/lib/colors.js
@@ -11,7 +11,8 @@ const plain = {
   30: nocolor,
   20: nocolor,
   10: nocolor,
-  message: nocolor
+  message: nocolor,
+  greyMessage: nocolor
 }
 
 const chalk = require('chalk')
@@ -24,7 +25,8 @@ const colored = {
   30: ctx.green,
   20: ctx.blue,
   10: ctx.grey,
-  message: ctx.cyan
+  message: ctx.cyan,
+  greyMessage: ctx.grey
 }
 
 function colorizeLevel (level, colorizer) {
@@ -41,11 +43,13 @@ function plainColorizer (level) {
   return colorizeLevel(level, plain)
 }
 plainColorizer.message = plain.message
+plainColorizer.greyMessage = plain.greyMessage
 
 function coloredColorizer (level) {
   return colorizeLevel(level, colored)
 }
 coloredColorizer.message = colored.message
+coloredColorizer.greyMessage = colored.greyMessage
 
 /**
  * Factory function get a function to colorized levels. The returned function
diff --git a/lib/utils.js b/lib/utils.js
index a365ff9b..ac8ac43d 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -307,7 +307,8 @@ function prettifyObject ({
   customPrettifiers = {},
   errorLikeKeys = ERROR_LIKE_KEYS,
   excludeLoggerKeys = true,
-  singleLine = false
+  singleLine = false,
+  colorizer = defaultColorizer
 }) {
   const keysToIgnore = [].concat(skipKeys)
 
@@ -334,7 +335,7 @@ function prettifyObject ({
   if (singleLine) {
     // Stringify the entire object as a single JSON line
     if (Object.keys(plain).length > 0) {
-      result += stringifySafe(plain)
+      result += colorizer.greyMessage(stringifySafe(plain))
     }
     result += eol
   } else {
diff --git a/test/lib/colors.test.js b/test/lib/colors.test.js
index 42674be3..166b8bad 100644
--- a/test/lib/colors.test.js
+++ b/test/lib/colors.test.js
@@ -34,6 +34,9 @@ test('returns default colorizer', async t => {
 
   colorized = colorizer.message('foo')
   t.is(colorized, 'foo')
+
+  colorized = colorizer.greyMessage('foo')
+  t.is(colorized, 'foo')
 })
 
 test('returns colorizing colorizer', async t => {
@@ -67,4 +70,7 @@ test('returns colorizing colorizer', async t => {
 
   colorized = colorizer.message('foo')
   t.is(colorized, '\u001B[36mfoo\u001B[39m')
+
+  colorized = colorizer.greyMessage('foo')
+  t.is(colorized, '\u001B[90mfoo\u001B[39m')
 })