About the Thread Pitch Calculator
Convert between thread pitch and threads per inch, with the standard metric coarse pitch.
Also known as: tpi to pitch, threads per inch, metric thread pitch, screw thread calculator.
How to use this calculator
- Enter i know the.
- 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
pitch (mm) = 25.4 ÷ threads per inch
Worked example
Using the values pre-filled in the calculator above:
- I know the: Metric bolt size
- Bolt size: M10
the calculator returns:
- Thread pitch: 1.5 mm
- Threads per inch: 16.933
- Thread height: 0.9201 mm
- Turns per 10 mm of travel: 6.667