Sandro, I recommend the free app "Vape Tool", which allows simply plugging in the wire gauges and material, and the app will give you a pretty close estimation...like the user above did. It can be quite useful by itself, but when you add Vape Tools' Eliquid calc., Ohms Law Calc., Battery Database, "Knowledge Zone", or Social Media site, you get a lot!

There are plenty of others, but I found Vape Tool to be the most full-featured with easiest navigation.

Also, check for similar wire spools from Vandy Vape. 100% guarantee they are made in the same factory, and the price should be cheaper, as Dovpo is dead-set on making BP Mods the Lexus to Dovpo's Toyota.