Appliance inputs come in BTU/h; pipe capacity tables speak in CFH. The bridge between the two is the heating value of the fuel - and it is not the same for natural gas and propane.
BTU to CFH Converter converts either way in one step.
BTU to CFH Converter
Convert between BTU per hour and cubic feet per hour for natural gas and propane, with the heating value of each fuel applied automatically. Instant two-way conversion.
Fuel
Convert
Enter either value - the other side fills itself. If both are filled, BTU/h wins.
Result
—
BTU/h
—
CFH
Notes
About BTU to CFH Converter
Features
- Two-way: BTU/h to CFH or CFH to BTU/h.
- Fuel aware: Natural gas or propane.
- Instant: Both sides update while you type.
- Live update: Results while you type.
- Export: Text, CSV or JSON report.
How to Use
- Choose the fuel (natural gas or propane).
- Enter a value in BTU/h or CFH.
- Read the converted value on the other side.
- Export the result if needed.
Examples
Example 1. A 180,000 BTU/h furnace on natural gas draws 1.8 CFH per 1,000 BTU - about 180 CFH.
Example 2. The same input on propane is only about 72 CFH because each cubic foot carries 2,516 BTU.
Benefits
- Fuel correct: NG and propane factors.
- Two-way: No manual maths.
- Instant: Live both-way conversion.
- Free and private: No uploads, no logging.
Frequently Asked Questions
What is a BTU?
A British Thermal Unit is the heat needed to raise one pound of water by one degree Fahrenheit. Gas appliances list their input in BTU per hour - the rate they consume fuel.
What is a CFH?
Cubic feet per hour - the volumetric flow of gas. Piping capacity tables are built in CFH, so converting the appliance BTU rating to CFH is the first step in sizing a gas line.
Why does the fuel matter?
Natural gas carries about 1,000 BTU per cubic foot at standard conditions; propane carries about 2,500. The same BTU load needs far fewer cubic feet of propane.
What is the standard heating value?
The calculator uses 1,000 BTU/ft3 for natural gas and 2,516 BTU/ft3 for propane, the common figures for sizing. Local gas varies slightly with composition and conditions.
Which direction can it convert?
Both. Enter BTU/h to get CFH, or enter CFH to get BTU/h - the active unit is whatever you filled in, and the other side updates instantly.
Is my data stored?
No. Everything runs in your browser; nothing is uploaded, saved or logged.
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