Abstract: An adjustable measuring device, including two segments pivotally joined at one end and having a measuring arc therebetween, at least one of the segments having an extending member capable of extending across the pivotal joint. The measuring arc provides the measure of angle between the two segments. Inner corners can be measured by placing the two segments against the surfaces defining the inner corner and reading the measuring arc. By extending at least one of the extending members across the pivotal joint, the angle of outer corners can also be measured in a similar manner.