Convert Kilograms-force per Square Millimetre to Kilopascals

Formula

kPa = kgf/mm² × 9806.65

Derivation from SI units:

• 1 kgf/mm² = 9.80665 N ÷ 1 mm² = 9.80665 MPa (exact)
• 1 kPa = 10³ Pa
• 1 kgf/mm² = 9806650 Pa ÷ 1000 Pa per kPa = 9806.65 kPa

Both units are defined exactly, so the factor is exact. Kilogram-force per Square Millimetre definition: kilogram-force per square millimetre; Kilopascal definition: kilopascal.

Worked examples

1. A reading of 24 kgf/mm² converts to 235359.6 kPa.
   24 kgf/mm² × 9806.65 = 235359.6 kPa
2. A value of 50 kgf/mm² is 490332.5 kPa.
   50 kgf/mm² × 9806.65 = 490332.5 kPa

Where it's used

Kilograms-force per Square Millimetre are used for tensile strength in older JIS and GB steel standards, while kilopascals appear in tyre pressure outside the United States (about 200–250 kPa for cars). Both measure pressure, stress and differential pressure (force per unit area), so the conversion is a fixed factor.

Kilogram-force per Square Millimetre to other pressure units

Frequently asked questions

Sources

• Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "kilogram-force per square millimeter".
• The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 7, SI prefixes.

Last reviewed: 2026-10-15. Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.