Gas Meter Reading to kWh Calculator (m³ or 100 ft³ to Energy)
The kWh and the cost of the gas you used between two meter readings, from the volume on the meter, the calorific value on your bill and the correction factor.
Results
What this tool does
A gas meter counts volume but the supplier bills energy, and the link is kWh = volume × correction factor × calorific value. The calorific value is printed on your bill and is typically around 10–12 kWh per cubic metre for natural gas (a figure quoted in MJ/m³ is divided by 3.6 to get kWh). Imperial meters count hundreds of cubic feet, and 100 ft³ is 2.83 m³. The correction factor adjusts the metered volume for the pressure and temperature of the gas; the UK uses 1.02264, while elsewhere it is often folded into the calorific value, in which case leave it at 1.
Formula
kWh = (reading 2 − reading 1) × (2.8317 if 100 ft³) × correction × calorific value (kWh/m³) · kWh/m³ = MJ/m³ ÷ 3.6
Variables
| Symbol | Meaning | Unit |
|---|---|---|
r1 | Previous meter reading | — |
r2 | Current meter reading | — |
u | Your meter counts in | — |
cv | Calorific value on your bill | kWh/m³ |
cf | Volume correction factor (1 if none) | — |
d | Days between the readings | d |
pr | Gas price per kWh | — |
KW | Energy billed | kWh |
V | Gas used | m³ |
C | Cost of the gas | — |
KD | Energy per day | kWh |
Worked example
- Previous meter reading1250
- Current meter reading1320
- Your meter counts in1
- Calorific value on your bill11.1 kWh/m³
- Volume correction factor (1 if none)1
- Days between the readings30 d
- Gas price per kWh0.1
- Energy billed777.0 kWh
- Gas used70.00 m³
- Cost of the gas77.70
- Energy per day25.9 kWh
Limitations
- Coverage and consumption figures vary between products. Take the values from the manufacturer's datasheet for the product you are actually using.
- Prices and emission factors are yours to enter. The tool ships with no tariff table and assumes nothing about your country or supplier, so change the defaults to match your own bill.