The amount you pay is based on Stamp Duty bands. The tax is calculated on the part of the property price falling in each band.
It'll work out how much Stamp Duty you'll need to pay, whether you're a first-time buyer, just moving to a new home having bought a house before, or if you're buying an additional property.
All you need is the property price and an idea of when your house sale might complete.
Dimension Estates Ltd calculator will give you an estimate of what your monthly payments would be for a particular loan amount, interest rate and mortgage type.