Yes, on both tiers, and there is no guest lane, no anonymous try. The free Demo signs you in exactly as paid Premium does; neither will open a certification exam for anyone who has not logged in. The account is less a gate than a filing system — it is where your attempts, your saved reviews, and any Premium you hold are gathered under one identity, so the work has an owner. Opening one is free and quick. The only thing not on offer is practicing without one.
The Demo is where this surprises people, since a free sample sounds like it should ask for nothing. What it asks for is a sign-in, and only that: the ten questions still produce a score and a review you can return to, and those need a place to sit. That place is the account.
One Account Across Unrelated Certification Exams
This carries more weight on CertFun than on a single-vendor site, because the exams here have little in common with one another. A Splunk SIEM paper and an ABA banking-compliance one test different worlds entirely, yet your work on both files into the same account and reads back as a single record. Attempts, saved reviews, and any Premium you buy attach to that one login rather than to a device or a browser, which is what lets you reopen a sitting from weeks and a different vendor ago and find it intact. Take the login away, and none of that has anything to hang on.