The length of your playtime in Persona 5 will depend largely on how much time you put into optional content, such as the game's prevalent social features.
At a minimum, you should expect to spend 70 hours in Persona 5 before you finish the calendar year. This is assuming that you speed through the story and are either very fast in combat or play on an easier difficulty.
Most players will be at around the 80 to 90 hour mark before they complete the game for their first time.
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