What SWG to mm calculator does
The SWG to mm calculator on RapidTables converts Standard Wire Gauge (SWG) measurements into metric diameters in millimeters. Users enter a specific gauge number and receive the corresponding wire diameter, cross-sectional area in square millimeters, and diameter in inches. This provides a quick way to translate imperial-based gauge sizes into the metric units commonly used in modern electrical wiring and component design. The RapidTables version stands out for its comprehensive reference chart and multiple output formats. Beyond the basic conversion, the page displays a full table of SWG sizes alongside their millimeter diameters and cross-sectional areas, plus a formula for calculating area from diameter. A dropdown selector allows users to pick from a wide range of gauges, from 7/0 down to 50, and the interface shows both metric and imperial measurements side-by-side, which is more detailed than many single-output converters.
How to use the RapidTables SWG to mm calculator
- 1
Select the desired SWG number from the dropdown menu or enter a specific gauge value
- 2
View the calculated diameter in millimeters displayed prominently on the page
- 3
Check the additional outputs for cross-sectional area in mm² and diameter in inches if needed
- 4
Reference the conversion chart below for quick lookups of other common SWG sizes
Best for
Electricians, engineers, and hobbyists who need to translate SWG measurements into metric millimeters for design verification, component selection, or working with electrical systems that use metric standards.
Limitations
- Results are based on established SWG standards and may not match every proprietary wire specification
- No option to input custom wire specifications or adjust calculation parameters
- Primarily designed for solid wire gauges; stranded wire constructions may vary
SWG to mm calculator FAQ
- Can this calculator handle AWG instead of SWG?
- No, this tool specifically converts Standard Wire Gauge (SWG) values. AWG (American Wire Gauge) is a different standard with different diameter measurements, so the results would not be accurate for AWG sizes.
- What if I need to convert from millimeters back to SWG?
- RapidTables does not list a reverse calculator on this page, but the provided chart of SWG diameters in millimeters can be used to estimate the corresponding SWG size by finding the closest match.
- Does the calculator account for stranded wire construction?
- The tool provides diameters based on standard SWG tables for solid wire. Stranded wire with the same total cross-sectional area will typically have a larger overall diameter due to the gaps between individual strands.
- Is there a limit to the SWG numbers I can enter?
- The interface includes a dropdown selector ranging from 7/0 down to 50, so values outside this range would need to be referenced against the full conversion chart or calculated using the provided formula.