diff --git a/src/Beutl.Core/Validation/RangeDataAnnotationValidater.cs b/src/Beutl.Core/Validation/RangeDataAnnotationValidater.cs
index 37b339b20..e4e19ca43 100644
--- a/src/Beutl.Core/Validation/RangeDataAnnotationValidater.cs
+++ b/src/Beutl.Core/Validation/RangeDataAnnotationValidater.cs
@@ -38,8 +38,27 @@ public RangeDataAnnotationValidater(RangeAttribute attribute)
 
     public override bool TryCoerce(ValidationContext context, ref TNumber value)
     {
-        value = TNumber.Clamp(value, Minimum, Maximum);
-        return true;
+        switch ((Attribute?.MaximumIsExclusive, Attribute?.MinimumIsExclusive))
+        {
+            case (true, true):
+                return false;
+
+            case (true, false):
+                value = TNumber.Max(value, Minimum);
+                return true;
+
+            case (false, true):
+                value = TNumber.Min(value, Maximum);
+                return true;
+
+            case (false, false):
+                value = TNumber.Clamp(value, Minimum, Maximum);
+                value = TNumber.Min(value, Maximum);
+                return true;
+
+            default:
+                return false;
+        }
     }
 
     public override string? Validate(ValidationContext context, TNumber value)
diff --git a/src/Beutl.Core/Validation/TupleRangeDataAnnotationValidater.cs b/src/Beutl.Core/Validation/TupleRangeDataAnnotationValidater.cs
index b1c852b24..3d483d40b 100644
--- a/src/Beutl.Core/Validation/TupleRangeDataAnnotationValidater.cs
+++ b/src/Beutl.Core/Validation/TupleRangeDataAnnotationValidater.cs
@@ -10,6 +10,9 @@ public sealed class TupleRangeDataAnnotationValidater<TTuple, TNumber> : RangeVa
 {
     public TupleRangeDataAnnotationValidater(RangeAttribute attribute)
     {
+        if (attribute.MaximumIsExclusive || attribute.MinimumIsExclusive)
+            throw new NotSupportedException("'MaximumIsExclusive' or 'MinimumIsExclusive' cannot be set to True.");
+
         Attribute = attribute;
         if (Attribute.OperandType == typeof(TTuple)
             && Attribute.Maximum is string maximumStr