Calculator

NPT pipe threader calculator

Enter nominal NPT inches. Get a 100 / 125 / 200 class or NO_MATCH. Match NPT size not OD alone; cut oil; square ends; PPE; depressurize.

Result

Enter values to begin.

Worked checks: 0.75 in → 100 · 1.25 in → 125 · 1.5 in → 200 · 2.5 in → NO_MATCH. classLbs uses 100 / 125 / 200 for CTA matching.

Guides

Limits, NPT matching, and when to stop shopping this ladder.