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Circle Punch Calculator

A simple tool for arc, chord, rise, and punch spacing calculations.

Pick your two known values

Select any two — arc, chord, or rise — and we’ll calculate the third.

Diagram of a circular segment showing its arc, chord and rise θ O

Dashed outline: the full circle · O marks its center · hover or select a row on the left to highlight it here

Enter the value

Type the value and choose its unit — we’ll show it in every unit as you go.

  • Millimeters—
  • Inches—
  • Meters—
  • Feet—
Diagram of a circular segment showing its arc, chord and rise θ O

Dashed outline: the full circle · O marks its center · the highlighted part is the value you’re entering

Review your values

Check everything below before we calculate your results.

Arc length

Chord length

Rise

Diagram of a circular segment showing its arc, chord and rise θ O

Dashed outline: the full circle · O marks its center · the highlighted parts are the values you entered

Your results

Here’s the full picture.

Punch distance —
Number of punches —
How many punch marks fit evenly along the arc.
Start margin (each end) —
Diagram of a circular segment showing its arc, chord and rise θ O

Dashed outline: the full circle · O marks its center · the shaded arc, chord and rise correspond to the readout on the left