diff --git a/package-lock.json b/package-lock.json
index 92de4f8f..bfc2e26e 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "nbdime-top-repo",
-  "version": "4.0.0-alpha.0",
+  "version": "4.0.0-rc.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "nbdime-top-repo",
-      "version": "4.0.0-alpha.0",
+      "version": "4.0.0-rc.0",
       "workspaces": [
         "packages/*"
       ],
@@ -22322,7 +22322,7 @@
     },
     "packages/labextension": {
       "name": "nbdime-jupyterlab",
-      "version": "3.0.0-alpha.2",
+      "version": "3.0.0-rc.0",
       "license": "BSD-3-Clause",
       "dependencies": {
         "@jupyterlab/apputils": "^4.0.0",
@@ -22338,7 +22338,7 @@
         "@lumino/coreutils": "^2.1.2",
         "@lumino/disposable": "^2.1.2",
         "@lumino/widgets": "^2.3.0",
-        "nbdime": "^7.0.0-alpha.2"
+        "nbdime": "^7.0.0-rc.0"
       },
       "devDependencies": {
         "@jupyterlab/application": "^4.0.0",
@@ -22367,7 +22367,7 @@
       }
     },
     "packages/nbdime": {
-      "version": "7.0.0-alpha.2",
+      "version": "7.0.0-rc.0",
       "license": "BSD-3-Clause",
       "dependencies": {
         "@codemirror/lang-markdown": "^6.1.1",
@@ -22417,7 +22417,7 @@
     },
     "packages/webapp": {
       "name": "nbdime-webapp",
-      "version": "4.0.0-alpha.0",
+      "version": "4.0.0-rc.0",
       "license": "BSD-3-Clause",
       "dependencies": {
         "@fortawesome/fontawesome-free": "^5.12.0",
@@ -22435,7 +22435,7 @@
         "@lumino/widgets": "^2.0.0",
         "alertify.js": "^1.0.12",
         "file-saver": "^2.0.1",
-        "nbdime": "^7.0.0-alpha.0"
+        "nbdime": "^7.0.0-rc.0"
       },
       "devDependencies": {
         "@types/file-saver": "^2.0.0",
diff --git a/package.json b/package.json
index 4fc5ff31..48d531c9 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "nbdime-top-repo",
-  "version": "4.0.0-alpha.0",
+  "version": "4.0.0-rc.0",
   "private": true,
   "workspaces": [
     "packages/*"
diff --git a/packages/labextension/package.json b/packages/labextension/package.json
index 318c1675..3e2d9e8f 100644
--- a/packages/labextension/package.json
+++ b/packages/labextension/package.json
@@ -1,6 +1,6 @@
 {
   "name": "nbdime-jupyterlab",
-  "version": "3.0.0-alpha.2",
+  "version": "3.0.0-rc.0",
   "description": "A JupyterLab extension for showing Notebook diffs.",
   "keywords": [
     "jupyter",
@@ -58,7 +58,7 @@
     "@lumino/coreutils": "^2.1.2",
     "@lumino/disposable": "^2.1.2",
     "@lumino/widgets": "^2.3.0",
-    "nbdime": "^7.0.0-alpha.2"
+    "nbdime": "^7.0.0-rc.0"
   },
   "devDependencies": {
     "@jupyterlab/application": "^4.0.0",
diff --git a/packages/nbdime/package.json b/packages/nbdime/package.json
index d7588965..a82f78e2 100644
--- a/packages/nbdime/package.json
+++ b/packages/nbdime/package.json
@@ -1,6 +1,6 @@
 {
   "name": "nbdime",
-  "version": "7.0.0-alpha.2",
+  "version": "7.0.0-rc.0",
   "description": "Diff and merge of Jupyter Notebooks",
   "repository": {
     "type": "git",
diff --git a/packages/webapp/package.json b/packages/webapp/package.json
index 09f40f2b..dee228d1 100644
--- a/packages/webapp/package.json
+++ b/packages/webapp/package.json
@@ -1,6 +1,6 @@
 {
   "name": "nbdime-webapp",
-  "version": "4.0.0-alpha.0",
+  "version": "4.0.0-rc.0",
   "private": true,
   "license": "BSD-3-Clause",
   "main": "static/nbdime.js",
@@ -27,7 +27,7 @@
     "@lumino/widgets": "^2.0.0",
     "alertify.js": "^1.0.12",
     "file-saver": "^2.0.1",
-    "nbdime": "^7.0.0-alpha.0"
+    "nbdime": "^7.0.0-rc.0"
   },
   "devDependencies": {
     "@types/file-saver": "^2.0.0",