diff --git a/js/id/core/graph.js b/js/id/core/graph.js
index 772206122..20d114bce 100644
--- a/js/id/core/graph.js
+++ b/js/id/core/graph.js
@@ -251,6 +251,16 @@ iD.Graph.prototype = {
         });
     },
 
+    revert: function(entity) {
+        if (this.entities[entity.id] === this.base().entities[entity.id])
+            return this;
+
+        return this.update(function() {
+            this._updateCalculated(entity, this.base().entities[entity.id]);
+            delete this.entities[entity.id];
+        });
+    },
+
     update: function() {
         var graph = this.frozen ? iD.Graph(this, true) : this;
 
diff --git a/test/spec/core/graph.js b/test/spec/core/graph.js
index d5238270d..65c4c76cb 100644
--- a/test/spec/core/graph.js
+++ b/test/spec/core/graph.js
@@ -334,28 +334,83 @@ describe('iD.Graph', function() {
             expect(graph.replace(w1).parentWays(node)).to.eql([w1]);
         });
 
-        it("adds parentRels",  function () {
+        it("adds parentRelations",  function () {
             var node = iD.Node({id: 'n' }),
-            r1 = iD.Relation({id: 'w', members: [{id: 'n'}]}),
-            graph = iD.Graph([node]);
+                r1 = iD.Relation({id: 'r', members: [{id: 'n'}]}),
+                graph = iD.Graph([node]);
             expect(graph.replace(r1).parentRelations(node)).to.eql([r1]);
         });
 
         it("removes parentRelations",  function () {
             var node = iD.Node({id: 'n' }),
-            r1 = iD.Relation({id: 'w', members: [{id: 'n'}]}),
-            graph = iD.Graph([node, r1]);
+                r1 = iD.Relation({id: 'r', members: [{id: 'n'}]}),
+                graph = iD.Graph([node, r1]);
             expect(graph.remove(r1).parentRelations(node)).to.eql([]);
         });
 
         it("doesn't add duplicate parentRelations",  function () {
             var node = iD.Node({id: 'n' }),
-            r1 = iD.Relation({id: 'w', members: [{id: 'n'}]}),
-            graph = iD.Graph([node, r1]);
+                r1 = iD.Relation({id: 'r', members: [{id: 'n'}]}),
+                graph = iD.Graph([node, r1]);
             expect(graph.replace(r1).parentRelations(node)).to.eql([r1]);
         });
     });
 
+    describe("#revert", function () {
+        it("is a no-op if the entity is identical to the base entity", function () {
+            var n1 = iD.Node({id: 'n' }),
+                graph = iD.Graph([n1]);
+            expect(graph.revert(n1)).to.equal(graph);
+        });
+
+        it("returns a new graph", function () {
+            var n1 = iD.Node({id: 'n' }),
+                n2 = n1.update({}),
+                graph = iD.Graph([n1]).replace(n2);
+            expect(graph.revert(n2)).not.to.equal(graph);
+        });
+
+        it("doesn't modify the receiver", function () {
+            var n1 = iD.Node({id: 'n' }),
+                n2 = n1.update({}),
+                graph = iD.Graph([n1]).replace(n2);
+            graph.revert(n2);
+            expect(graph.entity(n2.id)).to.equal(n2);
+        });
+
+        it("reverts the entity to the base version", function () {
+            var n1 = iD.Node({id: 'n' }),
+                n2 = n1.update({}),
+                graph = iD.Graph([n1]).replace(n2);
+
+            expect(graph.entity('n')).to.equal(n2);
+            graph = graph.revert(n2);
+            expect(graph.entity('n')).to.equal(n1);
+        });
+
+        it("reverts parentWays",  function () {
+            var n1 = iD.Node({id: 'n' }),
+                w1 = iD.Way({id: 'w', nodes: ['n']}),
+                w2 = w1.removeNode('n'),
+                graph = iD.Graph([n1, w1]).replace(w2);
+
+            expect(graph.parentWays(graph.entity('n'))).to.eql([]);
+            graph = graph.revert(w2);
+            expect(graph.parentWays(graph.entity('n'))).to.eql([w1]);
+        });
+
+        it("reverts parentRelations",  function () {
+            var n1 = iD.Node({id: 'n' }),
+                r1 = iD.Relation({id: 'r', members: [{id: 'n'}]}),
+                r2 = r1.removeMembersWithID('n'),
+                graph = iD.Graph([n1, r1]).replace(r2);
+
+            expect(graph.parentRelations(graph.entity('n'))).to.eql([]);
+            graph = graph.revert(r2);
+            expect(graph.parentRelations(graph.entity('n'))).to.eql([r1]);
+        });
+    });
+
     describe("#update", function () {
         it("returns a new graph if self is frozen", function () {
             var graph = iD.Graph();