The flag is 12 parts by 18, the white and red stripe are both 6 parts. The centre of the circle is set 7 parts from the hoist along the dividing line between the white and red, the radius being 4 parts. The upper part of the circle is red, the lower white.
Editor's note: Greenland 1985 law says the flag is determined by (Danish) Royal Resolution, however I cannot locate any such resolution.
Organization Erfalasorput, a national organisation dedicated to the flag, provides a confusing an inconsistent specification (e.g. two different red color values). The construction sheet however is clear, if with aethestically displeasing rations.
Flags of the World rely on an unsighted 1995 brochure containing a description from the flag's designer. I have opted to use the latter as it is more readily traced back to the original designer and maintains a more standard aspect ratio.