diff --git a/index.d.ts b/index.d.ts
index 8353c5a..bfa5e32 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -77,6 +77,9 @@ declare namespace WAWebJS {
         /** Check if a given ID is registered in whatsapp */
         isRegisteredUser(contactId: string): Promise<boolean>
 
+        /** Get the registered WhatsApp ID for a number. Returns null if the number is not registered on WhatsApp. */
+        getNumberId(number: string): Promise<ContactId?>
+
         /**
          * Mutes the Chat until a specified date
          * @param chatId ID of the chat that will be muted
diff --git a/src/Client.js b/src/Client.js
index 0aa30be..8560094 100644
--- a/src/Client.js
+++ b/src/Client.js
@@ -712,6 +712,26 @@ class Client extends EventEmitter {
         }, id);
     }
 
+    /**
+     * Get the registered WhatsApp ID for a number. 
+     * Will return null if the number is not registered on WhatsApp.
+     * @param {string} number Number or ID ("@c.us" will be automatically appended if not specified)
+     * @returns {Promise<Object|null>}
+     */
+    async getNumberId(number) {
+        if(!number.endsWith('@c.us')) {
+            number += '@c.us';
+        }
+
+        try {
+            return await this.pupPage.evaluate(async numberId => {
+                return window.WWebJS.getNumberId(numberId);
+            }, number);
+        } catch(_) {
+            return null;
+        }
+    }
+
     /**
      * Create a new group
      * @param {string} name group title
diff --git a/src/util/Injected.js b/src/util/Injected.js
index 9460c03..0e15e90 100644
--- a/src/util/Injected.js
+++ b/src/util/Injected.js
@@ -34,6 +34,7 @@ exports.ExposeStore = (moduleRaidStr) => {
 
 exports.LoadUtils = () => {
     window.WWebJS = {};
+
     window.WWebJS.getNumberId = async (id) => {
 
         let result = await window.Store.Wap.queryExist(id);
@@ -41,6 +42,7 @@ exports.LoadUtils = () => {
             throw 'The number provided is not a registered whatsapp user';
         return result.jid;
     };
+
     window.WWebJS.sendSeen = async (chatId) => {
         let chat = window.Store.Chat.get(chatId);
         if (chat !== undefined) {
@@ -50,6 +52,7 @@ exports.LoadUtils = () => {
         return false;
 
     };
+    
     window.WWebJS.sendMessage = async (chat, content, options = {}) => {
         let attOptions = {};
         if (options.attachment) {