Radiator BTU Calculator

Quickly and easily calculate the radiator heat output required to heat a room using our BTU (British Thermal Units) calculator.

How many BTU are needed to heat room?

Step 1

Step 2

What are the dimensions of your room?

Step 3

Which type of windows & doors do you have?


What size radiators do I need?

Every radiator on soak.com is given a BTU rating which we have highlighted on each product page.

The required BTU level to heat your room will influence the size of your radiators, but do not fear, we have numerous options for you to choose from. It definitely helps to consider the space that you have before making a final decision

High output radiators

How you know what radiator heat output you need, you can choose a radiator output that helps you achieve the goldilocks effect - not too hot, not too cold but just right!

View our full range of high BTU radiators or scroll through our pick of high output radiators below.