diff --git a/src/ExCSS.Tests/PropertyTests/FlexPropertyTests.cs b/src/ExCSS.Tests/PropertyTests/FlexPropertyTests.cs
index 887ee15d..78a862e1 100644
--- a/src/ExCSS.Tests/PropertyTests/FlexPropertyTests.cs
+++ b/src/ExCSS.Tests/PropertyTests/FlexPropertyTests.cs
@@ -26,5 +26,19 @@ public void JustifyAlign_Parses()
             Assert.Equal(@"center", info.Style.AlignSelf);
             Assert.Equal(@"center", info.Style.JustifyContent);
         }
+
+        [Fact]
+        public void FlexAuto_Parses()
+        {
+            string css = """
+html {
+    flex: auto;
+}
+""";
+
+            var stylesheet = new StylesheetParser().Parse(css);
+            var info = stylesheet.StyleRules.First() as ExCSS.StyleRule;
+            Assert.Equal(@"1 1 auto", info.Style.Flex);
+        }
     }
 }
diff --git a/src/ExCSS/Model/Converters.cs b/src/ExCSS/Model/Converters.cs
index ece72d2b..d450bb21 100644
--- a/src/ExCSS/Model/Converters.cs
+++ b/src/ExCSS/Model/Converters.cs
@@ -353,7 +353,7 @@ public static readonly IValueConverter
 
         public static readonly IValueConverter FlexConverter = Construct(() =>
         {
-            var flexGrow = FlexGrowShrinkConverter.WithFallback(0).For(PropertyNames.FlexGrow);
+            var flexGrow = FlexGrowShrinkConverter.WithFallback(1).For(PropertyNames.FlexGrow);
             var flexShrink = FlexGrowShrinkConverter.WithFallback(1).For(PropertyNames.FlexShrink);
             var flexBasis = FlexBasisConverter.WithFallback(0).For(PropertyNames.FlexBasis);