Gas Cost Calculator
Estimate the cost of gas usage from kWh, meter readings, cubic metres or cubic feet. This calculator can include unit rate, standing charge, calorific value and correction factor, making it useful for checking gas bills, boiler usage, heating costs and household budgeting.
Calculate gas cost
Choose whether you already know your gas usage in kWh, or whether you want to estimate kWh from gas meter units. For UK gas bills, suppliers usually convert meter units into kWh using volume, correction factor and calorific value.
Quick examples
| Meter units used | — |
| kWh per day | — |
| Cost per day | — |
| Estimated monthly cost | — |
| Estimated yearly cost | — |
| Rate used | — |
How it works
If you enter gas usage directly in kWh, the calculator multiplies that by your gas unit rate. If you enter meter readings, it first works out the meter units used, converts the volume into kWh using a correction factor and calorific value, then calculates the cost. Standing charge is added separately because it is a fixed daily charge rather than a usage charge.
Formula used
imperial meter kWh = units used × 2.83 × correction factor × calorific value ÷ 3.6
usage cost = kWh used × price per kWh
standing charge cost = daily standing charge × number of days
total cost = usage cost + standing charge cost
The 2.83 factor converts hundreds of cubic feet into cubic metres. The correction factor and calorific value are normally shown on your gas bill.
Worked example
Example: 10 m³ of gas at 6p/kWh
kWh = 111.34 kWh
usage cost = 111.34 × £0.06 = £6.68
So, using 10 cubic metres of gas at 6p/kWh costs about £6.68, excluding standing charge.
Common mistakes
Confusing meter units with kWh
Gas meters usually record volume, but gas bills charge energy in kWh. Meter units must be converted first.
Choosing the wrong meter type
Metric and imperial gas meters use different conversion steps. Check whether your meter reads m³ or ft³.
Forgetting standing charge
Standing charge can be a noticeable part of the bill, especially when usage is low.
Using an old tariff
Gas prices change. Use the unit rate and standing charge from your latest bill or tariff information.
Common questions
Why is gas billed in kWh?⌄
How do I know if my gas meter is metric or imperial?⌄
Should I include standing charge?⌄
Why might my bill be different?⌄
Sources, assumptions and disclaimer
This calculator is for general gas cost estimation. It uses the readings, rates, correction factor and calorific value you enter. It does not fetch live tariffs, replace your supplier’s bill calculation or guarantee your final bill.
- Unit rate: enter your latest gas unit rate from your bill or tariff.
- Standing charge: this is treated as a fixed daily cost and added separately.
- Calorific value: this can vary and is normally shown on your gas bill.
- Correction factor: many UK bills use 1.02264, but check your bill for the figure used.
- Disclaimer: this is an estimate only and is not financial, tariff, legal, energy-efficiency or gas-safety advice.