In energy and commodity trading, volumes and prices are quoted in many different units. This guide explains how to move between them—from barrels to tonnes, cubic metres to Btu—so you can read reports, compare markets, and speak the same language as traders and analysts.
Markets use different conventions: US oil in barrels, European gas in cubic metres, power in megawatt-hours, and global statistics in tonnes of oil equivalent (toe). Conversion factors are approximate numbers that let you translate one unit into another. They are essential for aggregation, reporting, and comparing supply and demand across regions and fuels.
All factors are approximate and based on widely used industry references. Actual density and energy content vary by grade and region.
A single barrel of crude holds about 159 litres. At roughly 7.33 barrels per tonne, a large tanker carrying 1 million tonnes is moving over 7 million barrels—enough to fill hundreds of Olympic swimming pools.
Crude is traded and reported in volume (barrels, kilolitres) and mass (tonnes). The link between them depends on density; the numbers below use a typical worldwide average.
One barrel (bbl) is 42 US gallons, or about 159 litres. One tonne of crude (at average gravity) is roughly 7.33 barrels or 1.165 kilolitres. Use these when moving between US-style (bbl) and metric (t, kL) reporting.
| From | To tonnes | To barrels | To kilolitres |
|---|---|---|---|
| 1 tonne | 1 | ≈ 7.33 | ≈ 1.165 |
| 1 barrel | ≈ 0.136 | 1 | ≈ 0.159 |
| 1 kilolitre | ≈ 0.858 | ≈ 6.29 | 1 |
Crude density varies by API gravity and region. Heavy crudes have more mass per barrel; light crudes less. The factors above follow a common industry average; for a specific grade, use its stated density or a regional standard.
Refined products have different densities and energy content per barrel or tonne. Conversion factors let you switch between volume, mass, and energy (e.g. gigajoules or barrels of oil equivalent).
Many reports use “barrel of oil equivalent” to compare different fuels on a common basis. One boe is typically defined as the energy in one barrel of crude: about 5.8 million Btu or 6.1 gigajoules.
Each product has its own conversion from barrels or tonnes to energy. For example, gasoline and diesel have different densities and heating values. When you see “tonnes of gasoline” or “barrels of diesel,” use product-specific factors from your data source or a standard reference to convert to GJ or boe.
| Product | Barrels → tonnes (approx) | Energy per barrel (approx) |
|---|---|---|
| Motor gasoline | ~0.12 t/bbl | ~5.3–5.5 GJ |
| Gas/diesel oil | ~0.13 t/bbl | ~5.9–6.0 GJ |
| Residual fuel oil | ~0.14 t/bbl | ~6.3–6.5 GJ |
Typical references list factors for ethane, LPG, motor gasoline, kerosene, gas/diesel oil, and residual fuel oil. Always check which standard your report uses (e.g. net vs gross calorific value).
Gas is reported in volume (cubic metres, cubic feet), energy (Btu, joules), and often in oil-equivalent (toe or boe). LNG is quoted in cubic metres or tonnes; conversion to energy uses heating value and density.
One billion cubic metres (bcm) of natural gas is often converted to about 0.86 million tonnes of oil equivalent (Mtoe). One trillion Btu is about 0.025 Mtoe. These factors depend on the heating value of the gas (which varies by source); the figures here are widely used approximations.
| Unit | Approx. to Mtoe | Notes |
|---|---|---|
| 1 bcm | ≈ 0.86 | Billion m³ natural gas |
| 1 billion ft³ | ≈ 0.024 | Bcf |
| 1 trillion Btu | ≈ 0.025 | Common in US reports |
LNG is natural gas cooled to liquid form. It is traded in cubic metres (liquid) or tonnes. Conversion to energy uses the heating value of the regasified product; typical references give factors from million tonnes LNG to bcm or to Mtoe. Check whether your source uses gross or net calorific value.
Power is measured in watts and energy in watt-hours (e.g. kWh, MWh). To compare with fossil fuels, electricity is often converted to primary energy using a thermal efficiency factor.
One kilowatt-hour (kWh) equals 3,600 kilojoules (kJ), about 3,412 Btu, and about 860 kilocalories. The tonne of oil equivalent (toe) is a common global yardstick: one toe is about 41.87 gigajoules, or roughly 11.63 MWh.
| Unit | Btu | kJ | kWh |
|---|---|---|---|
| 1 kWh | ≈ 3,412 | 3,600 | 1 |
| 1 Btu | 1 | ≈ 1.055 | ≈ 0.000293 |
| 1 toe | ≈ 39.68 M | ≈ 41.87 G | ≈ 11,630 |
M = million Btu; G = gigajoules (kJ × 10⁹).
When statistics show “primary energy” from non-fossil electricity (e.g. wind, solar), the physical electricity output is converted back to an equivalent amount of primary energy using a thermal efficiency factor—often in the range of about 36–40%. That reflects the average efficiency of thermal power plants; it lets different energy sources be compared on a common basis in reports like the Statistical Review of World Energy.
Enter a value and choose units to see approximate conversions. Useful for getting a feel for how barrels, tonnes, and energy relate.
Uses the approximate factor: 1 tonne ≈ 7.33 barrels.
1 kWh ≈ 0.003412 million Btu (or 3,412 Btu).