R1-1/4 vs 1/16-27 NPT: specs compared

Updated 05 September 2026.

41.91 mm
R1-1/4 wins on major diameter

On major diameter, R1-1/4 leads: 41.91 mm versus 7.94 mm.

SpecR1-1/41/16-27 NPT
DesignationR1-1/41/16-27 NPT
Major diameter41.91 mm7.94 mm
Threads per inch / pitch1127
Thread formtapered, 55 degreetapered, 60 degree
Seals onon the thread flanks with PTFE tape or pasteon the thread flanks with PTFE tape

Questions and answers

Which has the higher major diameter, R1-1/4 or 1/16-27 NPT?

On major diameter, R1-1/4 leads: 41.91 mm versus 7.94 mm.

How do R1-1/4 and 1/16-27 NPT compare?

On major diameter, R1-1/4 leads: 41.91 mm versus 7.94 mm.

Compared here