Blue Curve IV belongs to a group of five paintings of similar scale made in 1972. Each contains a radial curve painted in a single color against a white or black ground, sweeping from the lower left to the upper right of a nearly square canvas. Kelly was methodical in preparing the series. A study indicates the length of the radius for each curve; the longer the radius, the gentler the curve’s slope.

Blue Curve IV, with its vivid arc of azure blue set against a white ground, is a striking example of Kelly's paintings of single geometric forms. While its stark geometry is characteristic of his mid-career paintings, his formal exploration of the curve dates to the beginning of his career, including the simple curve he drew for Line Form Color in 1951. The same radius used for Blue Curve IV in 1972 appears again in Curve II, a large-scale steel sculpture created the following year.

Blue Curve IV can be seen as an indication of the direction Kelly’s work would take in later years. Similar curved shapes in blue can be found in works made in a variety of mediums and a wide range of sizes, from the 1984 postcard collage Summer (Blue Curve) to large multipanel paintings such as Blue Relief with Black (1993).