Unit Conversion Reference

Conversion factors across SI and US customary units for process engineering calculations.

Interactive Converter

Enter a value and select units — result calculates automatically

Quick Reference

Common Engineering Conversion Factors

Multiply	By	To Get
atmospheres	14.696	psi
barrels (petroleum)	42	US gallons
barrels (petroleum)	5.6146	cubic feet
BTU	778.16	ft·lbf
BTU/hr	0.29307	watts
cubic feet	7.48052	US gallons
cubic feet of water	62.4	pounds (at 60°F)
feet of water	0.4335	psi
gallons of water	8.345	pounds (at 60°F)
horsepower	33000	ft·lb/min
horsepower	2545	BTU/hr
horsepower	0.7457	kW
inches of mercury	0.4912	psi
inches of water	0.03613	psi
psi	2.311	feet of water (SG=1)
psi	27.73	inches of water
psi	2.036	inches of mercury
square feet	144	square inches
tons (refrigeration)	12000	BTU/hr
watts	3.412	BTU/hr

Source: Unit_Conversion_Tool_v1.xlsx

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