Praise be to Allah, and may peace and blessings be upon the Messenger of Allah. To proceed:
Yes, Al-Kabir (The Most Great) is one of the Beautiful Names of Allah established in the Noble Qur’an. Allah has named Himself by this name in several verses, including His saying:
“Knower of the unseen and the visible, the Most Great, the Most Exalted.”
Ar-Ra‘d: 9.
And He, Glorified be He, says:
“And He is the Most High, the Most Great.”
Saba’: 23.
What does the name of Allah “Al-Kabir” mean?
The name Al-Kabir indicates that Allah Almighty is greater than everything and greater than every created being. He is perfect in His Essence, His Names, His Attributes, and His Actions, and none of His creation is comparable to Him.
For this reason, Allah has prescribed for His servants to glorify and magnify Him. He says:
“And proclaim His greatness abundantly.”
Al-Isra’: 111.
Takbir (saying “Allahu Akbar”) has also been prescribed in prayer, the call to prayer, the two Eids, and other acts of worship.
Conclusion
Al-Kabir is one of the Beautiful Names of Allah established in the Noble Qur’an, and it is permissible to call Allah by this name as stated in the Islamic texts. It means that Allah is greater, more majestic, and higher than everything, and He alone is deserving of complete glorification and reverence.
And Allah knows best.