hex dimension calculator

What this hex dimension calculator does

This tool helps you move between the most common regular hexagon measurements used in design, machining, architecture, and fabrication. Instead of manually converting each dimension, you can enter one known value and calculate all the rest in one click.

The three most common input dimensions are:

• Side length (s): length of any one side of the hexagon.
• Across flats (AF): distance between two opposite parallel sides (commonly used for hex nuts and wrench sizes).
• Across corners (AC): distance between opposite vertices (tip-to-tip).

Core formulas for a regular hexagon

Once side length is known, everything else follows directly. If you start with across flats or across corners, this calculator first converts to side length, then computes all remaining dimensions.

When to use each dimension

• Across flats: best for mechanical parts, fasteners, and tool fit.
• Across corners: useful for clearances and outer envelope checks.
• Side length: convenient for geometric layouts, tiling, and drafting.

Practical example

Suppose you are designing a hex plate and only know the across flats dimension is 30 mm. The calculator converts that to side length (about 17.3205 mm), then gives you perimeter, tip-to-tip span, and area for cost estimation and material planning.

Tips for accurate results

• Use consistent units throughout (mm, cm, in, etc.).
• For manufacturing, round values according to your tolerance stack.
• If this is a real part, include chamfers/fillets separately; geometric formulas assume perfect vertices.
• Area is shown in square units (for example, mm²).

Final note

A regular hexagon is one of the most useful shapes in engineering and design because it packs efficiently and offers clean dimensional relationships. Keep this calculator bookmarked for quick conversions whenever you need fast, reliable hex geometry.