The Revised NEO Personality Inventory, also known as NEO PI-R, consists of 240 items designed to assess the Big Five personality dimensions. It typically requires 60 to 90 minutes to finish and is not timed.
The NEO Five-Factor Inventory (NEO-FFI) is a more concise version with just 60 items. It evaluates the same Big Five personality factors, allocating 12 questions per factor. This shorter test can be completed in approximately 10 to 15 minutes and is also untimed.