Essential unit conversions for engineering disciplines including force, pressure, energy, power, and more. This guide covers the most common engineering units, conversion tables, and practical examples.
Introduction
Engineers often work with a variety of unit systems, especially when collaborating internationally or using legacy data. Mastering unit conversions is crucial for accuracy and safety in engineering projects.
Force Conversions
Unit
Equivalent
Conversion
1 newton (N)
0.2248 pound-force (lbf)
N × 0.2248 = lbf
1 pound-force (lbf)
4.448 newtons (N)
lbf × 4.448 = N
Pressure Conversions
Unit
Equivalent
Conversion
1 pascal (Pa)
0.000145 psi
Pa × 0.000145 = psi
1 bar
14.5038 psi
bar × 14.5038 = psi
1 atmosphere (atm)
101,325 Pa
atm × 101325 = Pa
1 psi
6,894.76 Pa
psi × 6894.76 = Pa
Energy Conversions
Unit
Equivalent
Conversion
1 joule (J)
0.2390 calories (cal)
J × 0.2390 = cal
1 joule (J)
0.000278 kilowatt-hours (kWh)
J × 0.000278 = kWh
1 kilojoule (kJ)
0.9478 BTU
kJ × 0.9478 = BTU
1 BTU
1,055 joules (J)
BTU × 1055 = J
Power Conversions
Unit
Equivalent
Conversion
1 watt (W)
0.00134 horsepower (hp)
W × 0.00134 = hp
1 horsepower (hp)
745.7 watts (W)
hp × 745.7 = W
Length & Area Conversions
Unit
Equivalent
Conversion
1 meter (m)
3.2808 feet (ft)
m × 3.2808 = ft
1 square meter (m²)
10.7639 square feet (ft²)
m² × 10.7639 = ft²
1 inch (in)
25.4 millimeters (mm)
in × 25.4 = mm
Example Engineering Conversions
Convert 500 N to lbf: 500 × 0.2248 = 112.4 lbf
Convert 2 bar to psi: 2 × 14.5038 = 29.01 psi
Convert 5 kJ to BTU: 5 × 0.9478 = 4.74 BTU
Tips for Engineers
Always check which unit system your data and equipment use.
Use consistent units throughout calculations to avoid costly mistakes.
For complex conversions, use engineering calculators or trusted software.
FAQ
Why are unit conversions critical in engineering? Incorrect conversions can lead to design failures, safety hazards, and financial loss.
What is the SI system? The International System of Units (SI) is the modern metric system used globally in science and engineering.
