According to a first aspect, the invention relates to a cutting tool, in particular for severing planar materials, such as paper, cardboard, films, strips, and mats, as well as bands, ropes, and similar material, comprising a gripping area and a tool head (23), wherein a guide channel (24) is formed between guide surfaces (25a, 25b) of the tool head (23), wherein the material to be cut can be fed to the cutting edge (S) of a blade (15) only through the guide channel (24). The invention is characterized in that the blade (15) can be moved between a safety position, in which a cutting edge (S) of the blade (15) is protected by a cover so as to be inaccessible to a user, and a cutting position, in which the cutting edge (S) is accessible only through the guide channel (24).