@sujata-kattimani No limits.
Here's a list of FusionAuth limits: https://fusionauth.io/docs/v1/tech/reference/limitations
From the "What's not limited" section:
All other objects and configuration, including but not limited to the following, are limited only by the resources of your system:
Users
Applications
Tenants
Roles
Groups
Identity Providers such as SAML or OIDC connections
API keys to allow for programmatic configuration of and interaction with FusionAuth
Supported languages/locales
Signing and verifying keys
MFA methods per user
You are, of course, limited by your resources. If you try to load 100M users into a FusionAuth instance running in 256M of RAM, there's no guarantees the server won't fall over.
Also, if you are using the Starter license, you have a limit on MAUs. But for all other editions, no limits on users.