4-5 cups seems about right.
I typically ingest about 8 cups of coffee throughout the day.
That's a close-to-full pot of coffee for me.
As some have mentioned, "cups" the measurement does not necessarily equate to "cup" a receptacle.
I only say this because, one or two coffees brings me to life in the morning.
After that, I start to basically sustain a prolonged professional panic attack of concentrated anxiety that is more or less a reason to not schedule meetings with me in the afternoon.

That is to say, a cup from say, Starbucks would come in the following sizes:

Demi: 3oz

Short: 8oz

Tall: 12oz

Grande: 16oz

Venti: 20 oz

Trenta: 31 oz

In the US, to my knowledge:
1 cup : 8oz : 16 tbsp.

Typically, when I make 8 cups of coffee in my coffee pot, I use 6 level tablespoons of coffee grounds, medium, medium-coarse-ish. It literally doesn't matter. You swing from Turkish coffee to Cowboy coffee, the importance is that you have a consistent way to produce your desired grind. Ground coffee is unacceptable, because it oxidizes too quickly since it all tends to come in bags that nobody ever seals those correctly, and mostly because if you drink coffee, you're already lazy in the morning.

As many in the scientific community are familiar, the US is one of the last holdovers of the imperial system.

What most do not know, is that there is even significant difference between how the US and UK measure a tbsp for instance.

US: 14.8 ml for tsbp
UK: 15.0 ml for tbsp

If you're making coffee, that's a huge difference.

Example:
My ideal ratio is about 6 US tbsp : 8 cups of water.

That's not for flavor – so much that, in the morning, my brain literally does not care about mathematics or physics or cooking or anything really – I want to dump an exact amount of water, pour an exact amount of coffee and have a consistent cup that I can then slowly improve upon if I have a satisfactory cup of coffee.

The difference between US and UK would be 6 * 14.8 and 6 * 15.0 = 88.8 ml vs 90.0 ml.

You might say, that is a negligible difference!

HOW DARE YOU. THIS IS COOKING. THIS IS TASTE. THIS IS CHEMISTRY, THIS IS SCIENCE. THIS IS MATH. TO ERR IS HUMAN, TO FORGIVE IS DIVINE, BUT TO NOT CARE IS DEMONIC.

Less confrontational: That's just for one measurement of say grounds or fluid. The conversion of difference in measurement can be applied to both grounds and water.

So let's just convert tbsp by itself between UK and US.

6 tbsp of level coffee grounds.
96 tbsp of water, at whatever quality Los Angeles tap water is, which is terrible.

6:96 = 0.0625

This is an arbitrary ratio which means absolutely nothing, but let's compare it to the UK version.

So we know that UK tbsp is slightly larger.
Exactly (15.0/14.8) ~ 10%?

Okay, so that would be...
(15.0/14.8) 6 = 6.08108108108
(15.0/14.8) * 96 = 97.2972972973

So notice, when you take the ratio, it is exactly the same. The terms cancel out, but you are making more coffee.
This stuff tends to matter more, at higher altitudes or various humidity.
Essentially, water is the most sensitive medium for variation in boiling and quality control.
This may seem trivial, in my personal experience – I'd rather have too little caffeine than too much.

Basically, I want exactly two cups to be satisfactory.
It has more to do with the experience of drinking coffee and taste than the actual 'boost'.
Programmers or statisicians, data scientists, machine learning engineers will understand – You'd rather have just 2 of something, than to round up to 3. Nobody pours 2~3 cups of coffee. Either they are satisfied with 2, or they're chugging 3.

In whatever-programming, we call this the domain of non-linear real arithmetic as a decidable language. As in, I decide to drink more coffee than not.

As someone who started drinking coffee heavily since a teenager to offset the fact that I have never been a morning person and never will be, while also trying balance professionalism towards working in different timezones where clients prefer to start their day with a meeting...

Yeah, 1-2 cups of coffee. 8oz exactly. I have Ikea mugs. Those are 8oz.
One to install my brain, another to calm it down.
The second-order effects of caffeine are not unsubtle.

Anything more? I am bull-riding an anxiety trip of wanting to simultaneously produce Berlin techno and the latest innovation in machine learning. Your Mileage May Vary.

For true scientific intuition and experimental honesty, observe the following video detailing what occurs when you drink a full jar of coffee:

https://www.youtube.com/watch?v=wpWVk3h2SA8