ThreadChaser

Internal / External Thread Identifier

ThreadChaser is the fastest way to identify an unknown thread — on the shop floor, in the field, or at the workbench. Simply measure the major diameter and pitch of any fastener or threaded component, enter the values, and ThreadChaser instantly searches its database of metric and imperial thread standards to find the closest matches. No more guessing, no more flicking through reference books, no more ordering the wrong tap or die.

Who it's for ThreadChaser is built for engineers, machinists, mechanics, maintenance technicians, and anyone who regularly works with threaded fasteners. Whether you're identifying a mystery bolt on a piece of imported machinery, matching a thread on a worn component, or specifying a tap drill size for a new hole, ThreadChaser gives you the answer in seconds.

What it covers: ISO Metric coarse and fine threads (M1 through M68) Unified National threads — UNC, UNF, and UNEF British Standard — BSW, BSF, and BSP With more standards being added regularly

What you get: Instant thread matching with a tolerance you control Pitch diameter and minor diameter for every result Recommended tapping drill sizes Internal and external thread modes Technical thread profile diagrams A full reference library of thread standards and formulas

How to use: Use a digital calliper to measure the major diameter or internal bore of the thread. Use a thread pitch gauge or ruler to measure the pitch (distance between thread crests). Enter both values, select your preferred standards, and hit Search. ThreadChaser ranks every match by how closely it fits your measurement.

Terms of Use: https://www.threadchaser.com/TERMS