It's very simple. If you know the gross price of the price, including VAT, you have to divide the amount by 0.27. This is how you get the net value of the price. If you’re curious about the VAT itself, all you have to do is subtract the net price from the gross price and you’ll already get the VAT. That is, if the gross price is HUF 127, then 127x0.27 = 100 can be deducted . 127-100 = 27 If you know the net value of the price, the situation is even simpler because you only have to multiply the known amount by 1.27. That is, if the net value is 100, then 100x1.27 = 127 of course the difference between the gross and net value is VAT.