There is a Jira Standard API available to validate a Project Key (GET /rest/api/2/projectvalidate/key).
As per our requirement, we need to create a jira project programmatically through api's, we need to validate Jira Project Name.
For Jira Cloud, API is available to validate Jira Project Name(GET /rest/api/3/projectvalidate/validProjectName).
Not sure why its not made available for server/datacenter even though its a a valid case and frequently needed when any project needs to be created using APIs.
Thanks for the response but this lookup approach is time consuming(assume if there are more than 100 projects). Also there will be a separate implementation needed to check the formating and length of the project name. It will be better if API is provided for the same which does all the validation for the project name.