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Stress

N/mm²topsi

Convert newtons per square millimetre (stress) (N/mm²) to pounds-force per square inch (stress) (psi).

Factor1 N/mm² = 145.0377 psi

Converter

N/mm²

Accepts numbers or expressions, e.g. 150 + 14.7

Result
145.038psi

Rendered to 6 significant figures.

Formula

Formula
psi = N/mm² × 145.0377

Multiply any value in newtons per square millimetre (stress) by 145.0377 to obtain the value in pounds-force per square inch (stress).

Worked example

Convert 1 N/mm² to psi.

  1. 01Start with 1 N/mm².
  2. 02Multiply by the conversion factor: 1 × 145.0377 = 145.038 psi.
Result1 N/mm² = 145.038 psi

Conversion table

N/mm²psi
1145.04
2290.08
5725.19
101450.4
202900.8
507251.9
10014504
20029008
50072519
10001.4504e+5

Reference values rounded to 5 significant figures for display.

FAQ

What is the conversion factor from N/mm² to psi?
1 N/mm² equals 145.0377 psi. To convert, multiply the value in newtons per square millimetre (stress) by 145.0377.
How do I convert 1 N/mm² to psi?
1 N/mm² = 145.038 psi. For any value, multiply by 145.0377.
How do I convert psi back to N/mm²?
Divide by the same factor — or equivalently, multiply by 0.006894757. So 1 psi = 0.00689476 N/mm².
When would I need to convert newton per square millimetre (stress) to pound-force per square inch (stress)?
Stress conversions between N/mm² and psi are routine in mechanics-of-materials work: yield, ultimate and allowable-stress specification, Young's-modulus tables and structural-design code calculations. MPa and N/mm² dominate ISO and European datasheets, psi and ksi dominate US structural codes, and kgf/cm² and kgf/mm² appear in legacy JIS and heavy-engineering documentation. Stress is the same physical dimension as pressure but a different engineering quantity — this category is mechanics-of-materials, not process pressure.
Is the conversion exact?
The factor shown is precise to at least 7 significant figures. For most process-engineering work this is far better than instrument accuracy. For metrology or trade applications, refer to the relevant national standard (NIST, BIPM, ISO 80000).

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