diff --git a/meshroom/core/graph.py b/meshroom/core/graph.py
index bbf6960a..d92555a2 100644
--- a/meshroom/core/graph.py
+++ b/meshroom/core/graph.py
@@ -442,6 +442,13 @@ class Graph(BaseObject):
 
         return inEdges, outEdges
 
+    def upgradeAllNodes(self):
+        """ Upgrade all upgradable CompatibilityNode instances in the graph. """
+        nodeNames = [name for name, n in self._compatibilityNodes.items() if n.canUpgrade]
+        with GraphModification(self):
+            for nodeName in nodeNames:
+                self.upgradeNode(nodeName)
+
     @Slot(str, result=Attribute)
     def attribute(self, fullName):
         # type: (str) -> Attribute
diff --git a/meshroom/ui/commands.py b/meshroom/ui/commands.py
index a0a4e453..1c1a851c 100755
--- a/meshroom/ui/commands.py
+++ b/meshroom/ui/commands.py
@@ -270,6 +270,8 @@ class UpgradeNodeCommand(GraphCommand):
         self.setText("Upgrade Node {}".format(self.nodeName))
 
     def redoImpl(self):
+        if not self.graph.node(self.nodeName).canUpgrade:
+            return False
         inEdges, self.outEdges = self.graph.upgradeNode(self.nodeName)
         return True
 
diff --git a/meshroom/ui/graph.py b/meshroom/ui/graph.py
index 998e17b2..45bfd114 100644
--- a/meshroom/ui/graph.py
+++ b/meshroom/ui/graph.py
@@ -302,6 +302,14 @@ class UIGraph(QObject):
         """ Upgrade a CompatibilityNode. """
         self.push(commands.UpgradeNodeCommand(self._graph, node))
 
+    @Slot()
+    def upgradeAllNodes(self):
+        """ Upgrade all upgradable CompatibilityNode instances in the graph. """
+        with self.groupedGraphModification("Upgrade all Nodes"):
+            nodes = [n for n in self._graph._compatibilityNodes.values() if n.canUpgrade]
+            for node in nodes:
+                self.upgradeNode(node)
+
     @Slot(Attribute, QJsonValue)
     def appendAttribute(self, attribute, value=QJsonValue()):
         if isinstance(value, QJsonValue):
diff --git a/tests/test_compatibility.py b/tests/test_compatibility.py
index 541dbce6..307331ce 100644
--- a/tests/test_compatibility.py
+++ b/tests/test_compatibility.py
@@ -112,3 +112,40 @@ def test_description_conflict():
     assert hasattr(n, "in")
     # check uid has changed (not the same set of attributes)
     assert n.internalFolder != internalFolder
+    unregisterNodeType(SampleNodeV1)
+
+
+def test_upgradeAllNodes():
+    registerNodeType(SampleNodeV1)
+    registerNodeType(SampleNodeV2)
+
+    g = Graph('')
+    n1 = g.addNewNode("SampleNodeV1")
+    n2 = g.addNewNode("SampleNodeV2")
+    n1Name = n1.name
+    n2Name = n2.name
+    graphFile = os.path.join(tempfile.mkdtemp(), "test_description_conflict.mg")
+    g.save(graphFile)
+
+    # make SampleNodeV2 an unknown type
+    unregisterNodeType(SampleNodeV2)
+    # replace SampleNodeV1 by SampleNodeV2
+    meshroom.core.nodesDesc[SampleNodeV1.__name__] = SampleNodeV2
+
+    # reload file
+    g = loadGraph(graphFile)
+    os.remove(graphFile)
+
+    # both nodes are CompatibilityNodes
+    assert len(g.compatibilityNodes) == 2
+    assert g.node(n1Name).canUpgrade      # description conflict
+    assert not g.node(n2Name).canUpgrade  # unknown type
+
+    # upgrade all upgradable nodes
+    g.upgradeAllNodes()
+
+    # only the node with an unknown type has not been upgraded
+    assert len(g.compatibilityNodes) == 1
+    assert n2Name in g.compatibilityNodes.keys()
+
+    unregisterNodeType(SampleNodeV1)