A rotary tool includes a tool body having a driving end formed thereon and an annular groove defined therein. An indicating coiled spring is received in the annular groove. The indicating coiled spring has a colored indicating mark formed thereon for easily identifying a standard of the rotary tool. The indicating coiled spring is made of metal, wherein the indicating coiled spring is hard to be broken and a lifetime of the indicating coiled spring is lengthened. The indicating coiled spring is able to elastically expand to be easily and co-axially sleeved on the annular groove of the tool body, such that the indicating coiled spring being replaceable and re-useable. When operating, the indicating coiled spring is rotatable relative to the tool body.