One must take into account that there have not been any studies done on the absorption of nicotine from e-liquid when compared to regular cigarettes so the following math is approximate. Until we have definitive science to back everything up it's all a little bit of guess work and 'what works for you'. When figuring out the math, we must take into account that all cigarettes vary when it comes to nicotine content, holes in the filter, and other variables. As a general rule we can assume that regular cigarettes contain anywhere between 13mg and 18mg of nicotine. Thus, when burned, the total amount of nicotine in the smoke from a complete cigarette averages out to about 1mg. It does vary between 0.6 and 1.2mg, so average of 1 is good to go with for our purposes. So, with this math in mind, we can determine on average that we'll end up with the following cigarette equivalents;

- 6mg juice juice = ~0.6mg cigarette
- 12mg nicotine juice = ~0.8mg cigarette
- 18mg nicotine juice = ~1mg cigarette
- 24mg nicotine juice = ~1.2mg cigarette
- 36mg nicotine juice = ~1.8mg cigarette

So, if you smoke an average of 20 mild or medium cigarettes a day, you should get by fine with approximately ~1.0ml of 18mg juice per day.

- 1 mL = 200 puffs (equal to approximately 20 cigarettes or 1 pack of cigarettes)
- 30ml = 6000 puffs (equal to 600 cigarettes or 30 packs of cigarettes)

Basically, it's going to matter what works best for you and what helps you avoid analog cigarettes.