Adding auto incremental field

Hi All,

My form has a field named "new_siteid". The field should get auto populated onLoad with increments of 1.

For example: when a user creates a new record - site id will equal 000001.

Another record is created - site id = 000002 and so on.

Is there a way to accomplish this with js?

I've read somewhere to not use real time workflow method because it will not give you a unique number when you do imports or two users save a record at the same time.

Thank you,