About Gas Bill Calculator
A small, independent tool built to make a fiddly calculation easier to check.
Gas Bill Calculator began in 2011 after a shared household bill needed splitting. Finding the meter usage was easy; turning it into a trustworthy cost was not. The first version was a single-page calculator made to solve that problem.
It has since grown into a practical guide to meter readings, gas conversions and the charges on a UK bill. The purpose has stayed the same: show the working, keep the language plain and let people use the tool without opening an account.
How the calculator works
The calculation runs in your browser. It subtracts the readings, converts the metered volume to kWh and applies the tariff figures you provide. The results separate usage, standing charge and VAT so they are easier to compare with a supplier’s statement.
Our calculation guide sets out the method, worked examples and rounding assumptions so you can check the result yourself.
How the site is funded
The site is independent and self-funded. Advertising helps pay for hosting, maintenance and the time spent keeping the calculator and guides up to date. Gas Bill Calculator is not an energy supplier or price-comparison service, and calculator results do not favour a supplier.
Accuracy and limits
The calculator is an estimate, not a replacement bill. Suppliers may use a slightly different calorific value, round at different stages or change rates during a billing period. If a result looks wrong, check the meter type, dates, tariff rates and whether VAT is already included.
Corrections and feedback
Energy prices and guidance change. Each time-sensitive page shows when its figures were checked and links to the underlying source. If you spot something that needs correcting, please get in touch.