About the Screw Size Calculator
Metric and imperial screw dimensions — major, minor and pitch diameters plus clearance holes.
Also known as: screw dimensions, metric screw chart, screw gauge to mm, screw diameter.
How to use this calculator
- Enter screw size.
- The result updates instantly as you type — press Calculate (or Enter) at any time.
- Review the breakdown shown under the main result.
- Use Copy result or Share to save the answer or send a link with your inputs.
Formula
minor diameter = D − 1.0825 × pitch
Worked example
Using the values pre-filled in the calculator above:
- Screw size: M6
the calculator returns:
- Major diameter: 6 mm
- Pitch diameter: 5.351 mm
- Minor diameter: 4.918 mm
- Tap drill: 5 mm