diff --git a/src/openjd/model/_range_expr.py b/src/openjd/model/_range_expr.py
index 7c789945..33df5288 100644
--- a/src/openjd/model/_range_expr.py
+++ b/src/openjd/model/_range_expr.py
@@ -150,6 +150,10 @@ def ranges(self) -> list[IntRange]:
 
     def _validate(self) -> None:
         """raises: ValueError - if not valid"""
+        if len(self) > 1024:
+            raise ValueError(
+                f"Range expression produces {len(self)} values, but the maximum is 1024."
+            )
         # Validate that the ranges are not overlapping
         prev_range: IntRange | None = None
         for range_ in self.ranges:
diff --git a/test/openjd/model/_internal/test_range_expr.py b/test/openjd/model/_internal/test_range_expr.py
index f79d2ade..e8984fdc 100644
--- a/test/openjd/model/_internal/test_range_expr.py
+++ b/test/openjd/model/_internal/test_range_expr.py
@@ -362,6 +362,30 @@ def test_contains(self) -> None:
         assert -3 not in IntRangeExpr.from_str("-1--2:-1")
         assert 0 not in IntRangeExpr.from_str("-1--2:-1")
 
+    def test_range_expr_max_1024_items_succeeds(self):
+        expr = IntRangeExpr.from_str("1-1024")
+        assert len(expr) == 1024
+
+    def test_range_expr_1025_items_fails(self):
+        with pytest.raises(ExpressionError):
+            IntRangeExpr.from_str("1-1025")
+
+    def test_range_expr_combined_subranges_exceed_1024_fails(self):
+        with pytest.raises(ExpressionError):
+            IntRangeExpr.from_str("1-600,700-1300")
+
+    def test_range_expr_stepped_within_limit_succeeds(self):
+        expr = IntRangeExpr.from_str("1-2047:2")
+        assert len(expr) == 1024
+
+    def test_range_expr_stepped_exceeds_limit_fails(self):
+        with pytest.raises(ExpressionError):
+            IntRangeExpr.from_str("1-3000:2")
+
+    def test_range_expr_negative_range_exceeds_limit_fails(self):
+        with pytest.raises(ExpressionError):
+            IntRangeExpr.from_str("-512-512")
+
 
 class TestIntRange:
     def test_length(self):