Unit converter

Fuel Efficiency - Volume converter

Convert energy-per-volume units including joules per cubic meter, BTU per cubic foot, and therms.

Enter a value and choose units. Results update instantly.

1 J/m³ = 0.001 kJ/m³

All Fuel Efficiency - Volume units

From 1 J/m³
UnitValue
Joule/cubic meter J/m³ 1
Kilojoule/cubic meter kJ/m³ 0.001
Megajoule/cubic meter MJ/m³ 0.000001
Kilocalorie/cubic meter kcal/m³ 0.0002388459
Therm/cubic foot therm/ft³ 0.0000000003
Btu/cubic foot Btu/ft³ 0.0000268392
Btu/cubic inch Btu/in³ 0.0000001556
Btu/gallon (US) Btu/gal (US) 0.0000035879
Recent conversions
  1. Your recent conversions stay on this device.

Common tasks

Joule/cubic meter to Kilojoule/cubic meterJ/m³ to kJ/m³ Kilojoule/cubic meter to Joule/cubic meterkJ/m³ to J/m³ Joule/cubic meter to Megajoule/cubic meterJ/m³ to MJ/m³ Megajoule/cubic meter to Joule/cubic meterMJ/m³ to J/m³ Joule/cubic meter to Kilocalorie/cubic meterJ/m³ to kcal/m³ Kilocalorie/cubic meter to Joule/cubic meterkcal/m³ to J/m³

Reference

How fuel efficiency - volume conversion works

Volume-based fuel energy density compares available energy with fuel volume. Values are normalized to Joule/cubic meter before conversion to the requested output unit.

Values are converted to joule/cubic meter first, then from that reference into the requested unit. Keeping a single documented reference reduces inconsistent pair-by-pair constants.

Accuracy note: SI relationships follow the cited reference. Conventional and domain-specific factors use the established ConvertWin factor inventory; verify safety-critical work against the governing standard.

Unit reference

UnitSymbol1 unit in J/m³
Joule/cubic meterJ/m³1
Kilojoule/cubic meterkJ/m³1,000
Megajoule/cubic meterMJ/m³1,000,000
Kilocalorie/cubic meterkcal/m³4,186.8
Therm/cubic foottherm/ft³3,725,894,600
Btu/cubic footBtu/ft³37,258.946000000004
Btu/cubic inchBtu/in³6,426,573.5
Btu/gallon (US)Btu/gal (US)278,716.5

Long-tail directory

Every indexed conversion

Choose a source unit to see all available destinations.

From Joule/cubic meter (J/m³)
Joule/cubic meter to Kilojoule/cubic meterJoule/cubic meter to Megajoule/cubic meterJoule/cubic meter to Kilocalorie/cubic meterJoule/cubic meter to Therm/cubic foot
From Kilojoule/cubic meter (kJ/m³)
Kilojoule/cubic meter to Joule/cubic meterKilojoule/cubic meter to Megajoule/cubic meterKilojoule/cubic meter to Kilocalorie/cubic meterKilojoule/cubic meter to Therm/cubic foot
From Megajoule/cubic meter (MJ/m³)
Megajoule/cubic meter to Joule/cubic meterMegajoule/cubic meter to Kilojoule/cubic meterMegajoule/cubic meter to Kilocalorie/cubic meterMegajoule/cubic meter to Therm/cubic foot
From Kilocalorie/cubic meter (kcal/m³)
Kilocalorie/cubic meter to Joule/cubic meterKilocalorie/cubic meter to Kilojoule/cubic meterKilocalorie/cubic meter to Megajoule/cubic meterKilocalorie/cubic meter to Therm/cubic foot
From Therm/cubic foot (therm/ft³)
Therm/cubic foot to Joule/cubic meterTherm/cubic foot to Kilojoule/cubic meterTherm/cubic foot to Megajoule/cubic meterTherm/cubic foot to Kilocalorie/cubic meter

Primary source

Definitions and standards

The SI framework is checked against NIST Guide for the Use of the International System of Units. Conventional factors are retained from the extended ConvertWin inventory and carry the accuracy note shown above.

See Methods & sources for rounding rules, exact-value handling, and review policy.

Questions

Fuel Efficiency - Volume FAQ

What is the reference unit for fuel efficiency - volume conversions?

ConvertWin uses joule/cubic meter (J/m³) as the internal reference for this category, then converts to the selected output unit.

How accurate is this fuel efficiency - volume converter?

SI relationships follow the cited reference. Conventional and domain-specific factors use the established ConvertWin factor inventory; verify safety-critical work against the governing standard.