Engineering Unit Converter (Metric / Imperial)
Verified by Rachel Mayfield, Supply Chain Analyst - April 2026
Convert between metric and imperial units for length, force, torque, pressure, mass, flow, power, and temperature. Engineering Unit Converter (Metric / Imperial) Covers the conversions UK engineers most commonly need when working with imported equipment specifications, US-spec drawings, or legacy plant.
Convert engineering units
Conversions based on BIPM SI definitions and NIST reference values. Temperature conversions use exact formulas: F = C * 9/5 + 32; K = C + 273.15.
Notes on engineering unit conversion
Temperature conversions use exact formulas (F = C x 9/5 + 32; K = C + 273.15). All other conversions are linear factors derived from SI base units. US and UK gallons differ: 1 US gallon = 3.785 litres; 1 UK gallon = 4.546 litres. When reading American hydraulic datasheets specified in gpm, confirm whether the number is US or UK gallons - the difference is 17% and can significantly affect sizing calculations.
Horsepower has multiple definitions. Metric horsepower (PS, ch) = 735.5 W. UK mechanical horsepower = 745.7 W. The difference is small (about 1.4%) but matters when specifying motor ratings. This calculator uses metric horsepower for EU specifications and UK mechanical horsepower for British datasheets.
References
- BIPM SI Brochure - SI unit definitions
- NIST Guide for the Use of SI - Conversion reference
Frequently Asked Questions
How do I convert Nm to lb-ft?
Multiply Nm by 0.737562 to get lb-ft. For example, 100 Nm = 73.76 lb-ft. To go the other way, multiply lb-ft by 1.35582.
How many psi in 1 bar?
1 bar = 14.5038 psi. 1 bar is also very close to 1 atmosphere (1.01325 bar = 1 atm) and 1 kgf/cm^2 (0.980665 bar). Use the precise 14.5038 factor for engineering calculations.
What is the difference between US and UK gallons?
A US gallon is 3.7854 litres; a UK (Imperial) gallon is 4.5461 litres. UK gallons are about 20% larger. When reading hydraulic or fuel flow specs, check which gallon is meant - the difference materially affects sizing.
What is the Engineering Unit Converter (Metric / Imperial) and how does it assist UK engineers?
The Engineering Unit Converter (Metric / Imperial) is a tool designed to help UK engineers convert between metric and imperial units for dimensions like length, force, torque, pressure, mass, flow, power, and temperature. It simplifies working with imported equipment specifications and US drawings.
What types of conversions can be performed using the Engineering Unit Converter (Metric / Imperial)?
This converter supports a variety of engineering unit conversions including length (like meters to feet), force (newtons to pounds-force), torque (newton-meters to foot-pounds), pressure (pascals to psi), mass (kilograms to pounds), flow rate (cubic meters per second to gallons per minute), power (watts to horsepower), and temperature (Celsius to Fahrenheit).
How do UK engineers choose the appropriate conversion type in the Engineering Unit Converter (Metric / Imperial)?
Engineers should select a category that matches the unit they wish to convert, such as 'Length' or 'Force'. Then, they choose the specific conversion within that category from the dropdown menu. For example, converting between meters and feet under the Length category.
Are there industry standards for metric and imperial conversions used by the Engineering Unit Converter (Metric / Imperial)?
Yes, the converter adheres to ISO standards such as ISO 31-1 for physical quantities and units which ensure consistency in unit conversion. This helps engineers maintain accuracy when working across different measurement systems.
Where can UK-based engineers find reliable suppliers or sources of the Engineering Unit Converter (Metric / Imperial)?
Reliable suppliers for the Engineering Unit Converter (Metric / Imperial) include software providers specializing in engineering tools, such as MathWorks and PTC. These companies offer strong conversion tools integrated into their full software suites.
What is the cost to access the Engineering Unit Converter (Metric / Imperial), and where can it be obtained?
Accessing the Engineering Unit Converter (Metric / Imperial) is often included in larger engineering software packages or available as a free web-based tool. For example, some providers offer basic versions for free while premium features require subscription payments.
Can the Engineering Unit Converter (Metric / Imperial) handle conversions involving less common units used by UK engineers?
Yes, it can handle a wide range of unit types including those that are less commonly used in everyday engineering tasks. For instance, it supports conversion between metric and imperial units for specific applications like converting between newton-meters and inch-pounds for torque measurements.