Dimension Radius

The dimradius command places a radius dimension on an arc or circle. The dimension line runs from the center to a point on the circumference in the cursor's direction, labeled R <value>. To dimension a full diameter instead, use Dimension Diameter.

Anatomy of a radius dimension

  ● (center)
   \
    \  R 5.00
     \
      ●────── text (cursor side)
   (arc point)

• Dimension line — from center through an arc point toward the cursor, with an arrowhead at the arc.
• Label — R followed by the radius value.

Placing a radius dimension

1. Type dimradius in the terminal or click the Dimension Radius toolbar button.
2. Click an arc or circle to select it.
3. Move the cursor to orient the dimension line — the arc-point tracks the cursor direction from the center.
4. Click to place the dimension.

Only Arc and Circle entities can be selected. Clicking any other entity type does nothing.

Keyboard reference

Key	Action
Escape	Cancel

Dimension Radius vs Dimension Diameter

	Dimension Radius	Dimension Diameter
Measures	Radius (center to edge)	Diameter (edge to edge through center)
Dimension line	Center → arc point	Arc point → arc point (through center)
Label prefix	R	⌀
Arrowheads	One (at arc point)	Two (at both arc points)
Best for	Annotating one side of a curved feature	Annotating full circular dimensions

DXF — DIMENSION radius entity

Radius dimensions are saved as DIMENSION entities with radius-type geometry, storing the center coordinates, the arc-point position, and the measured radius value. All properties round-trip without loss.