How to use the bolt circle hole spacing calculator
Find the spacing between holes evenly placed on a bolt circle. Enter bolt circle diameter, number of holes in the fields above; the spacing between adjacent holes, angle between holes are computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “bolt circle spacing”, “spacing of bolt holes”, “hole pattern distance”, “calculate bolt circle hole spacing”, “find spacing between adjacent holes”.
Formula
Variables
- D — Bolt circle diameter (mm)
- n — Number of holes
Worked example
With bolt circle diameter = 120 mm, number of holes = 6, the calculator gives spacing between adjacent holes ≈ 60 mm; angle between holes ≈ 60 °.
Frequently asked questions
What is the bolt circle hole spacing calculator used for?
Find the spacing between holes evenly placed on a bolt circle. It helps with questions such as “bolt circle spacing”, “spacing of bolt holes”, “hole pattern distance”.
What is the formula for the bolt circle hole spacing calculation?
Spacing between adjacent holes (mm) = D × sin(180 / n). Angle between holes (°) = 360 / n. Here D is bolt circle diameter (mm), n is number of holes.
What inputs do I need for the bolt circle hole spacing calculator?
You need bolt circle diameter in mm, number of holes. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the bolt circle hole spacing calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the bolt circle hole spacing result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.