BTU to Joules Converter
Convert energy between British thermal units and joules while keeping the International Table factor exact.
Conversion inputs
1 BTU = 1055.05585262 J (International Table). Swap direction to compute the reciprocal.
How to use
Choose the conversion direction and type the energy value you have. The calculator keeps the ratio precise to the International Table definition and formats the result automatically.
Methodology
The engine multiplies or divides by the IT factor 1 BTU = 1055.05585262 J, keeping rounding deterministic to six significant digits and falling back to exponential notation for extremes.
Full original guide (expanded)
Energy converter – BTU ↔ J
Switch between BTU and joules while the placeholder cues the right unit. The built-in swap button toggled before now makes it easy to jump back and forth.
The conversion note below the inputs reiterates the exact factor and clarifies that the reciprocal uses the inverse multiplier.
BTU vs BTU/hr: Energy versus power
While the current calculator focuses on energy, the broader suite also differentiates energy (BTU, J) from power (BTU/hr, W). Energy is the total amount stored or released, while power is the rate at which that energy moves.
- Energy: BTU and Joules measure the quantity of heat or work.
- Power: BTU/hr and Watts describe how fast the energy transfers.
Sample conversions
| BTU (Energy) | Joules (J) |
|---|---|
| 1 | 1,055 J |
| 100 | 105,506 J |
| 1,000 | 1.055 MJ |
| 10,000 | 10.55 MJ |
FAQ snapshot
What formula converts BTU to Joules? Multiply by 1055.05585262 (the precise IT factor). Divide by the same to go from Joules to BTU.
How many Joules are in 1 BTU? There are 1,055.056 Joules (≈1.055 kJ).
Why the energy vs power warning? Appliances rated in BTU/hr describe power, while the accumulated energy over time is billed in kWh or Joules.