Convenient-to-use female end diameter measurer

The invention belongs to the technical field of measuring tools, and particularly relates to the field of G01B5/08, in particular to an inner spigot diameter measurer convenient to use. The invention provides a convenient-to-use female end diameter measurer, which is characterized by comprising a sliding block, a fixed block and a meter fixing block, the sliding block and the fixed block tend to be away from each other, and the meter fixing block is arranged on the other side, opposite to the fixed block, of the sliding block; an adjustable sliding measuring head is fixedly arranged on the sliding block, and an adjustable fixed measuring head is fixedly arranged on the fixed block. According to the invention, the spring influencing the measurement precision is arranged in the cavity of the ruler rod, the spring sleeves the rod part of the sliding screw, and the two end parts and the two end face structures of the spring are fixedly connected, so that the spring is protected in all directions, the spring is pr