Hi @Shambhavi Rai · Thank you for reaching out.
There is no specific limit for App Registrations in a tenant. The limit is for overall number Directory Objects in a tenant, which includes, Users, Groups, Applications, servicePrincipals and so on.
The default Directory Objects limit is 50K, which gets extended to 300K when a verified domain is added to the tenant. You can get the limit further raised to 500K by opening a support ticket with Microsoft. If you have Azure AD Premium license, you can get is raised beyond 500K by providing business justification.
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