Abstract: A drill comprising: a drill main body; a chip discharge flute; and a tip cutting edge. The tip cutting edge includes: a first tip cutting edge which extends toward the axially posterior end as it goes toward the outside in a radial direction; and a second tip cutting edge which is disposed outside the first tip cutting edge in the radial direction. The second tip cutting edge extends toward the tip in the axis direction as it goes toward the outside in the radial direction or extends to be perpendicular to the axis. The radially inner end of the second tip cutting edge is disposed on the axially posterior end with respect to the radially outer end of the first tip cutting edge. The radially outer end of the second tip cutting edge is disposed on a virtual extension line of the first tip cutting edge.

Abstract: A drill including: a drill main body that rotates about an axis of the drill main body; a chip discharge groove formed on an outer periphery of a tip portion of the drill main body; and a cutting edge formed on the tip portion of the drill main body, a rake face of the cutting edge being a wall surface of the chip discharge groove facing a rotation direction of the drill is provided. The cutting edge includes: a major cutting edge portion provided on an inner peripheral side of the tip portion of the drill main body; a chamfer portion provided on a posterior outer-peripheral side relative to the major cutting edge portion; and a convex curved portion that is provided between the major cutting edge portion and the chamfer portion, the convex curved portion being directed toward a posterior end side of the drill main body from the inner peripheral side to the outer peripheral side with a convex curved shape viewed from a side facing the rake face.