Caliper-type brake measuring tape

The utility model discloses a caliper-type brake measuring tape, which comprises a shell, a tape strip, a tape spring and a brake mechanism, the tape strip is coiled in the shell, and the outer ring of the tape strip forms a straight section on the inner side of an extension port of the shell and extends out of the extension port; the brake mechanism comprises a push button installed on the shell in a sliding mode and a clamping assembly arranged in the shell. The clamping assembly comprises two clamping blocks symmetrically arranged on the two transverse sides of the straight section of the ruler strip and a screw penetrating through the two clamping blocks and rotationally installed on the inner wall of the shell. The two clamping blocks are connected with the screw rod through two sections of threads with opposite screwing directions; a gear is fixed on the screw rod, the push button sliding rail is tangent to the gear, and a ruler strip meshed with the gear is arranged on the push button; braking is carri