Fuel Weight Calculator – Convert Fuel Volume to Weight for Multiple Use Cases
Fuel is usually measured by volume at the pump or in a tank, but for loading, performance and safety you often need fuel weight. This Fuel Weight Calculator from MyTimeCalculator gives you four dedicated modes so you can convert fuel volume to weight for jet fuel, automotive fuel, marine fuel or any custom liquid.
Instead of memorizing densities and unit conversions, you only need to enter fuel volume, choose a fuel type and select your units. The calculator uses typical mid-range densities and returns fuel weight in kilograms and pounds, together with the density it used and the equivalent volume in liters.
How the Fuel Weight Calculator is Organized
The tool is split into four modes that match common real-world scenarios:
- Jet Fuel Weight: Jet-A, Jet-A1, Avgas 100LL and MOGAS gasoline with an approximate temperature correction.
- Automotive Fuel Weight: Gasoline, E10, diesel, E85 and LPG / propane in common units.
- Marine Fuel Weight: Diesel, marine diesel (MGO), heavy fuel oil (HFO) and custom specific gravity.
- Custom Density: Any liquid with a known density in kg/L, g/cm³ or lb/US gal.
All four modes share the same internal conversion engine so you can move between liters, US gallons, imperial gallons and cubic meters without touching a calculator.
Mode 1 – Jet Fuel Weight (Jet-A, Jet-A1, Avgas, MOGAS)
In aviation, fuel weight affects weight and balance, takeoff performance and range. This mode focuses on the most common aviation fuels:
- Jet-A: Typical density ≈ 0.804 kg/L.
- Jet-A1: Typical density ≈ 0.802 kg/L.
- Avgas 100LL: Typical density ≈ 0.721 kg/L.
- MOGAS / gasoline: Typical density ≈ 0.745 kg/L.
You enter fuel volume, choose US gallons, liters or imperial gallons, and optionally enter approximate fuel temperature in °C. The calculator applies a small linear correction around a 15 °C reference to estimate the density at that temperature. It then reports total fuel weight in kilograms and pounds, the density it used and the equivalent volume in liters.
Mode 2 – Automotive Fuel Weight (Gasoline, Diesel, E10, E85, LPG)
For cars, trucks and generators, you might want to know how much weight full tanks add or compare fuel loads between vehicles. This mode includes:
- Gasoline (E0) ≈ 0.745 kg/L
- Gasoline E10 ≈ 0.760 kg/L
- Diesel ≈ 0.832 kg/L
- E85 (approximate density between gasoline and ethanol)
- LPG / propane ≈ 0.493 kg/L
Enter fuel volume in gallons or liters and see the corresponding fuel weight. This is useful when checking trailer limits, calculating how much weight a long-range tank adds or estimating the impact of fuel on payload.
Mode 3 – Marine Fuel Weight (Diesel, MGO, HFO, Custom SG)
Ships and large vessels burn significant amounts of fuel, and fuel weight directly affects displacement, draft and trim. The marine mode works with:
- Standard diesel ≈ 0.832 kg/L
- Marine diesel oil (MGO) ≈ 0.860 kg/L
- Heavy fuel oil (HFO) ≈ 0.950 kg/L
- Any fuel specified by specific gravityative to water at 15 °C
In addition to liters and gallons, this mode accepts volume directly in cubic meters, which is common for bunker quantities. If you know a grade’s specific gravity, you can enter it and the calculator converts it into kg/L internally.
Mode 4 – Custom Density Fuel Weight Calculator
Sometimes you are working with experimental fuels, lab samples or fluids that are not standard gasoline or diesel. The custom density mode gives you full control:
- Enter volume in liters, US gallons, imperial gallons or cubic meters.
- Enter density in kg/L, g/cm³ or lb/US gal.
- Choose your preferred decimal precision.
The calculator converts everything onto a common basis, computes total weight in kilograms and pounds and tells you what kg/L density it used and the internal liter volume.
Typical Fuel Densities Used in This Calculator
Densities can vary with temperature, composition and grade, but this calculator uses typical mid-range values at 15 °C:
- Jet-A ≈ 0.804 kg/L (≈ 6.70 lb/US gal)
- Jet-A1 ≈ 0.802 kg/L (≈ 6.68 lb/US gal)
- Avgas 100LL ≈ 0.721 kg/L (≈ 6.00 lb/US gal)
- Gasoline (E0) ≈ 0.745 kg/L (≈ 6.21 lb/US gal)
- Gasoline E10 ≈ 0.760 kg/L (≈ 6.34 lb/US gal)
- Diesel ≈ 0.832 kg/L (≈ 6.94 lb/US gal)
- Marine diesel (MGO) ≈ 0.860 kg/L (≈ 7.17 lb/US gal)
- Heavy fuel oil (HFO) ≈ 0.950 kg/L (≈ 7.93 lb/US gal)
- LPG / propane ≈ 0.493 kg/L (≈ 4.11 lb/US gal)
If your operating environment uses different standard values, you can always switch to the custom density mode and plug in those numbers directly.
How to Use This Fuel Weight Calculator Effectively
- Choose the tab that best matches your use case: jet, automotive, marine or custom.
- Enter volume in the units you actually use (liters, gallons or cubic meters).
- Check that the default density values match your expectations; if not, use the custom tab.
- Use the result as a planning aid, not as the only input for safety-critical weight calculations.
For aviation, marine and industrial applications, always cross-check with official documentation, loading systems or engineering tools provided by manufacturers and regulators.
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Fuel Weight FAQs
Frequently Asked Questions Fuel Weight and Density
Quick answers to help you interpret your fuel weight results and choose the right mode.
Tanks, pumps and invoices usually talk in liters or gallons, but weight and balance, performance, draft and payload calculations work in kilograms or pounds. Density links volume and weight so you can understand the real impact of fuel on your vehicle, vessel or aircraft.
Fuel composition, temperature and local specifications all affect density. Even for a given grade like Jet-A or diesel, suppliers may publish slightly different standard densities. This calculator uses representative mid-range values, which are sufficient for estimates but may differ from your local standard by a few percent.
No. It uses a simple linear approximation around 15 °C to show the effect of warmer or cooler fuel on density and weight. Real fuel temperature compensation in professional contexts uses official tables and more detailed coefficients. Always follow your company or regulator’s procedures for operational use.
Yes. The custom density tab works for any liquid as long as you know its density in kg/L, g/cm³ or lb/US gal. You can use it for oils, chemicals or even water-based solutions when planning storage or transport weight.
No. It is intended for planning and educational use. Certified operations must always follow approved manuals, performance charts and digital tools specific to the aircraft, vessel or vehicle type.