diff --git a/package-lock.json b/package-lock.json
index 96d4850..814c6f6 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "aa-js",
-  "version": "3.6.3",
+  "version": "4.0.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
       "name": "aa-js",
-      "version": "3.6.3",
+      "version": "4.0.0",
       "license": "MIT",
       "dependencies": {
         "dayjs": "^1.11.6"
diff --git a/package.json b/package.json
index 973311a..4a1b5f9 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "aa-js",
-  "version": "3.6.3",
+  "version": "4.0.0",
   "description": "Astronomical Algorithms in Javascript",
   "files": [
     "dist/**/*.js",