diff --git a/comfy_api/latest/_io.py b/comfy_api/latest/_io.py
index 6c293b22d..4c062d8aa 100644
--- a/comfy_api/latest/_io.py
+++ b/comfy_api/latest/_io.py
@@ -1451,6 +1451,27 @@ class VideoEdit(ComfyTypeIO):
             })
 
 
+@comfytype(io_type="RESOLUTION_PREVIEW")
+class ResolutionPreview(ComfyTypeIO):
+    Type = dict
+
+    class Input(WidgetInput):
+        def __init__(self, id: str, display_name: str=None, optional=True, tooltip: str=None,
+                     socketless: bool=True, advanced: bool=None,
+                     ratio_widget: str="aspect_ratio", megapixels_widget: str="megapixels", multiple_widget: str="multiple"):
+            super().__init__(id, display_name, optional, tooltip, None, None, socketless, None, None, None, None, advanced)
+            self.ratio_widget = ratio_widget
+            self.megapixels_widget = megapixels_widget
+            self.multiple_widget = multiple_widget
+
+        def as_dict(self):
+            return super().as_dict() | prune_dict({
+                "ratio_widget": self.ratio_widget,
+                "megapixels_widget": self.megapixels_widget,
+                "multiple_widget": self.multiple_widget,
+            })
+
+
 @comfytype(io_type="HISTOGRAM")
 class Histogram(ComfyTypeIO):
     """A histogram represented as a list of bin counts."""
@@ -2529,5 +2550,6 @@ __all__ = [
     "Histogram",
     "Range",
     "VideoEdit",
+    "ResolutionPreview",
     "NodeReplace",
 ]
diff --git a/comfy_extras/nodes_resolution.py b/comfy_extras/nodes_resolution.py
index 083e47ae4..945a05538 100644
--- a/comfy_extras/nodes_resolution.py
+++ b/comfy_extras/nodes_resolution.py
@@ -52,6 +52,10 @@ class ResolutionSelector(io.ComfyNode):
                     step=0.1,
                     tooltip="Target total megapixels. 1.0 MP ≈ 1024x1024 for square.",
                 ),
+                io.ResolutionPreview.Input(
+                    "preview",
+                    tooltip="Live preview of the calculated output resolution.",
+                ),
                 io.Int.Input(
                     id="multiple",
                     default=8,
@@ -73,7 +77,7 @@ class ResolutionSelector(io.ComfyNode):
         )
 
     @classmethod
-    def execute(cls, aspect_ratio: str, megapixels: float, multiple: int) -> io.NodeOutput:
+    def execute(cls, aspect_ratio: str, megapixels: float, multiple: int, preview=None) -> io.NodeOutput:
         w_ratio, h_ratio = ASPECT_RATIOS[aspect_ratio]
         total_pixels = megapixels * 1024 * 1024
         scale = math.sqrt(total_pixels / (w_ratio * h_ratio))
diff --git a/tests-unit/comfy_api_test/resolution_preview_serialization_test.py b/tests-unit/comfy_api_test/resolution_preview_serialization_test.py
new file mode 100644
index 000000000..97a4633e3
--- /dev/null
+++ b/tests-unit/comfy_api_test/resolution_preview_serialization_test.py
@@ -0,0 +1,61 @@
+from comfy_api.latest._io import ResolutionPreview
+from comfy_extras.nodes_resolution import ResolutionSelector
+
+
+def test_resolution_preview_defaults_optional_and_socketless():
+    preview = ResolutionPreview.Input("preview")
+
+    assert preview.optional is True
+    assert preview.socketless is True
+
+
+def test_resolution_preview_serializes_default_widget_names():
+    serialized = ResolutionPreview.Input("preview").as_dict()
+
+    assert serialized["socketless"] is True
+    assert serialized["ratio_widget"] == "aspect_ratio"
+    assert serialized["megapixels_widget"] == "megapixels"
+    assert serialized["multiple_widget"] == "multiple"
+
+
+def test_resolution_preview_serializes_custom_widget_names():
+    serialized = ResolutionPreview.Input(
+        "preview",
+        ratio_widget="ratio",
+        megapixels_widget="mp",
+        multiple_widget="resolution_steps",
+    ).as_dict()
+
+    assert serialized["ratio_widget"] == "ratio"
+    assert serialized["megapixels_widget"] == "mp"
+    assert serialized["multiple_widget"] == "resolution_steps"
+
+
+def test_resolution_preview_carries_no_default_value():
+    serialized = ResolutionPreview.Input("preview").as_dict()
+
+    assert "default" not in serialized
+
+
+def test_resolution_selector_schema_exposes_optional_preview():
+    schema = ResolutionSelector.define_schema()
+    preview = next(i for i in schema.inputs if i.id == "preview")
+
+    assert preview.optional is True
+    assert str(preview.get_io_type()) == "RESOLUTION_PREVIEW"
+
+
+def test_resolution_selector_executes_without_preview():
+    """The frontend never sends the preview value in the API prompt."""
+    output = ResolutionSelector.execute("16:9 (Widescreen)", 1.0, 8)
+
+    assert output.result == (1368, 768)
+
+
+def test_resolution_selector_ignores_preview_value():
+    baseline = ResolutionSelector.execute("3:4 (Portrait Standard)", 2.0, 32)
+    with_preview = ResolutionSelector.execute(
+        "3:4 (Portrait Standard)", 2.0, 32, preview={"stale": True}
+    )
+
+    assert baseline.result == with_preview.result == (1248, 1664)