Hexagon Calculator
Calculate area, perimeter, diagonals, apothem, and circumradius of a regular hexagon.
Dimensions
Updates as you typeSolve from
Which measurement do you know? ?
Measurement
Side (s)
cm
—
Orientation (visual only)
Hexagon orientation ?
Formula
A
=
3√3
2
s2
P
=
6s
a
=
s√3
2
R
=
s
dlong
=
2s
dshort
=
s√3
- A
- Area of the hexagon
- P
- Perimeter — the sum of all six sides
- s
- Side length — all six sides are equal
- a
- Apothem — centre to midpoint of a side (inscribed-circle radius)
- R
- Circumradius — centre to any vertex (circumscribed-circle radius). For a regular hexagon, R = s.
- dlong
- Long diagonal — joins opposite vertices (passes through the centre)
- dshort
- Short diagonal — joins vertices two apart (parallel to a side)
Worked example — your numbers
- s = —
- s² = —
- Area = (3√3 / 2) · s² = —
- Perimeter = 6s = —
- Apothem = s√3 / 2 = —
- Circumradius = s = —
- Long diagonal = 2s = —
- Short diagonal = s√3 = —
The regular hexagon is six equilateral triangles glued around a common centre — which is why its area equals 6 · (s²√3 / 4) = (3√3 / 2) · s², and why the circumradius equals the side length exactly. Every interior angle is 120°, the complement that makes three hexagons tile a plane with no gaps.