How can I calculate the frame rate? I have some misunderstandings with deltaTime.

I feel a little embarrassed asking a simple question such as this so far along in my projects. But oddly, I did a search and came up empty. Thought for sure someone would have asked this question before.

Is there a simple formula for figuring out the frame rate so I can view it in my standalone game? I understand how Time.deltaTime works (insofar that it counts time rather than frames, and how to use it for accurate animation/simulation speeds on all platforms), but sometimes I have trouble figuring out what to do with it, so I have no idea what kind of equation I pop it into to count how many frames have passed since the last second, even with a full understanding that every time Update() runs, it means a frame has passed. Think I'm just confused.

Perhaps as an aside to help me understand deltaTime a bit better (I could just ask for code and be on my way, but I also want to solve the root of my misunderstanding) and a part two to my question... I saw a script that DaveA posted a week ago for someone asking for a script detecting double-tapping. I recall that the code basically did nothing but asked for a check on Time.deltaTime inside Update(). But how does that work if that check runs every single frame? Shouldn't it never detect a double-tap if the same check code is running fresh and new on every Update()?

I feel like maybe once I understand more practical applications of deltaTime and why it works, I might be able to clean up some of my scripts and invent my own solutions to certain problems, like my inability to calculate the frame rate on my own. :)

Without seeing the double-tap code, it's impossible to say. Time.deltaTime, as implied by the name, is simply the amount of time that has passed since the last frame.