That’s a great question to which there is no answer really.
How quickly you consume your e-juice will depend on a variety of things:
- What mod you use
- What clearomizer / atomizer you use
- Which coils you use
- What e-juice you use
- Your technique
- How much you use your e-cigarette
But the rule of thumb is that the more advanced setup you run, the more e-juice you will consume. You could, for example with no problem at all go through 10-15ml of e-juice per day if you are running the most advanced products: Mechanical mod or 200w-mod + RDA + advanced coil build. While if you run a simpler model and vape moderately a 10ml bottle of e-juice would be enough for you for a week or even longer.
So the answer is: There is no answer, it all depends on what you use and how you use it.