Conversion Formulas
1 MJ = 0.27778 kWh = 0.001 GJ
1 GJ = 277.78 kWh = 1000 MJ
These are exact conversions -- no rounding approximation involved.
Canadian Home Energy Consumption Reference
| Scenario | kWh | MJ | GJ |
|---|---|---|---|
| 1 kWh (single unit) | 1 | 3.6 | 0.0036 |
| Typical daily electricity use | 20 - 40 | 72 - 144 | 0.072 - 0.144 |
| Monthly electricity bill (average) | 600 - 1200 | 2 160 - 4 320 | 2.16 - 4.32 |
| Annual electricity (all-electric home) | 15 000 - 25 000 | 54 000 - 90 000 | 54 - 90 |
| Annual electricity (gas-heated home) | 6 000 - 9 000 | 21 600 - 32 400 | 21.6 - 32.4 |
| Total annual home energy (average Canadian) | 22 000 - 33 000 | 79 200 - 118 800 | 79.2 - 118.8 |
| EnerGuide 80 home (mid-efficiency) | ~22 200 | ~80 000 | ~80 |
| Net-zero ready home | ~5 500 - 11 000 | ~20 000 - 40 000 | ~20 - 40 |
Natural Gas to GJ Conversion Reference
| Natural Gas Volume | Energy Content | kWh Equivalent | Notes |
|---|---|---|---|
| 1 m³ | 37.3 MJ | 10.4 kWh | Typical Canadian heating value; check bill for exact factor |
| 100 m³ | 3.73 GJ | 1 036 kWh | Common monthly summer consumption |
| 1000 m³ | 37.3 GJ | 10 361 kWh | Common monthly winter heating consumption |
| 1 GJ (billing unit) | 1 GJ | 277.78 kWh | Standard unit on Alberta, BC, Manitoba gas bills |
Natural gas heating value varies slightly by gas composition and measurement conditions -- always use the conversion factor printed on your actual gas bill for precise accounting. Use the Energy Converter for BTU, therm, and kcal conversions as well.
How to Use the kWh to MJ Converter
Type an energy value in kWh, MJ, or GJ. All other units update instantly. Use the quick presets to load common Canadian energy quantities: 1 kWh, 1 GJ, typical annual electricity consumption, or the energy content of 1 cubic metre of natural gas.
The result panel identifies what scale of energy your value represents: a single appliance reading, a daily or monthly billing quantity, or an annual whole-home total. This helps confirm a converted value is in the right order of magnitude before entering it into an energy audit or EnerGuide comparison.
The home energy reference table covers everything from a single kWh through full annual consumption for all-electric, gas-heated, and high-performance homes. Use it to sanity-check your own utility bill data or EnerGuide rating against typical Canadian ranges.
Use the natural gas reference table to convert cubic metres of gas to GJ or kWh-equivalent for direct comparison against electricity usage. For BTU and therm conversions as well, use the Energy Converter, which covers the full range of energy units used across Canadian and North American HVAC and energy billing.
kWh, MJ, and GJ -- Canada's Core Energy Conversion
Converting between kWh and MJ (or GJ) is one of the most frequent tasks in Canadian energy audits, EnerGuide reporting, and utility bill analysis. Electricity is metered and billed in kWh across Canada. Natural gas is billed in GJ in several provinces, or in cubic metres with a GJ conversion shown on the bill in others. EnerGuide home ratings express total annual energy consumption in GJ regardless of fuel source, making this conversion foundational to Canadian energy work.
The Exact Conversion Factor: 3.6
Unlike many unit conversions that involve measured physical constants, kWh to MJ is a definitional exact conversion: 1 kWh is defined as exactly 3.6 megajoules, because 1 watt-hour equals 3600 joules (1 watt for 3600 seconds), and 1 kWh is 1000 times that. This means 1 kWh = 3.6 MJ with zero rounding error, a relationship confirmed in the NIST Guide to the SI, Appendix B. Scaling up: 1 GJ = 1000 MJ = 1000/3.6 kWh = 277.78 kWh.
EnerGuide and the GJ Standard
The EnerGuide rating system, administered by Natural Resources Canada, expresses a home's total annual energy consumption in gigajoules regardless of fuel mix. This allows an all-electric home in British Columbia to be compared fairly against a gas-heated home in Alberta, since both energy sources convert to the same GJ basis. An all-electric home using 20,000 kWh annually consumes 72 GJ (20,000 x 0.0036). A home using 8,000 kWh of electricity plus 70 GJ of natural gas consumes a total of 8,000 x 0.0036 + 70 = 28.8 + 70 = 98.8 GJ. The Energy Intensity Calculator works in this same GJ basis for benchmarking a home's total consumption against its floor area.
Comparing Electricity and Gas Costs
Converting both fuels to a common GJ basis allows direct cost-per-unit-energy comparison. Electricity at a typical Canadian rate converts to roughly $28 to $47 per GJ (0.10 to 0.17 dollars per kWh divided by 0.0036 GJ per kWh). Natural gas is typically priced lower per GJ in most Canadian markets. However, equipment efficiency matters -- a heat pump with a coefficient of performance (COP) of 3 delivers 3 GJ of heat per GJ of electricity consumed, which can make electric heating cost-competitive with gas despite the higher raw energy price. Use the COP / EER Converter and Energy Cost Calculator for full comparisons.
Reading Your Natural Gas Bill
Canadian natural gas bills show consumption either in cubic metres with a conversion factor to GJ, or directly in GJ. The conversion factor -- typically around 37.3 MJ per cubic metre but varying slightly by gas composition and season -- is usually printed directly on the bill. Multiply your metered cubic metres by this factor and divide by 1000 to get GJ, or use the factor directly if your utility already reports GJ. Once in GJ, you can convert to kWh-equivalent (multiply by 277.78) to compare directly against your electricity consumption on the same energy scale. The Canada Energy Regulator publishes annual data on what a typical residential gas bill actually contains.
Frequently Asked Questions
Multiply kWh by 3.6 to get MJ -- this is an exact conversion with no rounding involved. So 1 kWh = 3.6 MJ, 100 kWh = 360 MJ, and 1000 kWh = 3600 MJ = 3.6 GJ. To convert MJ back to kWh, divide by 3.6. This conversion is fundamental to Canadian energy audits since electricity is metered in kWh but EnerGuide and gas billing use MJ or GJ.
Multiply kWh by 0.0036 to get GJ. So 1000 kWh = 3.6 GJ, and 15,000 kWh = 54 GJ. To convert GJ back to kWh, multiply by 277.78. This is the key conversion for comparing your electricity bill against your EnerGuide rating, since EnerGuide expresses total home energy consumption in GJ regardless of fuel source.
Electricity is billed in kWh because that's the natural metering unit for electrical delivery. Natural gas is billed in GJ or cubic metres because gas volume and heating value are measured differently. Both are energy units and convert directly: 1 GJ = 277.78 kWh. This lets you compare electric heating costs against gas heating costs on a common energy basis, which is essential when deciding between heating fuel options or evaluating a heat pump conversion.
EnerGuide, administered by Natural Resources Canada, expresses total annual home energy consumption in gigajoules (GJ), combining electricity (converted from kWh at the 3.6 MJ/kWh factor) and any other fuels like natural gas or propane onto one scale. This allows fair comparison between homes using different fuel combinations. The national average Canadian home consumes roughly 80 to 120 GJ per year across all fuel sources.