Convert Millimeters of Water to Gigapascals (mmH2O to GPa)
1 millimeter of water (mmH₂O) = 9.80665 × 10⁻⁹ gigapascals (GPa). 1 GPa = 101971621.3 mmH₂O. Example: 15 mmH₂O = 15 × 9.80665 × 10⁻⁹ = 1.4709975 × 10⁻⁷ GPa.
Also searched as millimeters of water to GPa, millimeters of water in GPa, millimeters of water into gigapascals, mmH2O to GPa, mmH2O in gigapascals, mmH2O into gigapascal, millimeter of water to gigapascal, mmH2O to gigapascals converter, millimetres of water to gigapascals and how many gigapascals in a millimeter of water.
1 mmH₂O = 9.80665e-9 GPa
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk millimeter of water to gigapascal converter to paste a column from Excel.
How to Convert Millimeter of Water to Gigapascal
- 1 mmH₂O = 9.80665 × 10⁻⁹ GPa
- 1 GPa = 101971621.3 mmH₂O
- Example: convert 15 mmH₂O to GPa: 15 mmH₂O = 15 × 9.80665 × 10⁻⁹ GPa = 1.4709975 × 10⁻⁷ GPa
Reference conditions. mmH₂O: Conventional water column: ρ = 1000 kg/m³ and gₙ = 9.80665 m/s² (≈ water at 4 °C).
Formula
GPa = mmH₂O × 9.80665 × 10⁻⁹
or GPa = mmH₂O ÷ 101971621.2978
Derivation from SI units:
- 1 mmH₂O = 1000 kg/m³ × 9.80665 m/s² × 0.001 m = 9.80665 Pa
- 1 GPa = 10⁹ Pa = 1000 MPa = 1 kN/mm²
- 1 mmH₂O = 9.80665 Pa ÷ 1000000000 Pa per GPa = 9.80665 × 10⁻⁹ GPa
Both units are defined exactly, so the factor is exact. Millimeter of Water definition: millimeter of water; Gigapascal definition: gigapascal.
Worked examples
- A reading of 25 mmH₂O converts to 2.4516625 × 10⁻⁷ GPa.
25 mmH₂O × 9.80665 × 10⁻⁹ = 2.4516625 × 10⁻⁷ GPa - A value of 250 mmH₂O is 0.0000024516625 GPa.
250 mmH₂O × 9.80665 × 10⁻⁹ = 0.0000024516625 GPa
Millimeter of Water to Gigapascal conversion table
| Millimeters of Water (mmH₂O) | Gigapascals (GPa) |
|---|---|
| 1 mmH₂O | 9.80665 × 10⁻⁹ GPa |
| 2 mmH₂O | 1.96133 × 10⁻⁸ GPa |
| 5 mmH₂O | 4.903325 × 10⁻⁸ GPa |
| 10 mmH₂O | 9.80665 × 10⁻⁸ GPa |
| 15 mmH₂O | 1.4709975 × 10⁻⁷ GPa |
| 20 mmH₂O | 1.96133 × 10⁻⁷ GPa |
| 25 mmH₂O | 2.4516625 × 10⁻⁷ GPa |
| 30 mmH₂O | 2.941995 × 10⁻⁷ GPa |
| 50 mmH₂O | 4.903325 × 10⁻⁷ GPa |
| 75 mmH₂O | 7.3549875 × 10⁻⁷ GPa |
| 100 mmH₂O | 9.80665 × 10⁻⁷ GPa |
| 150 mmH₂O | 0.0000014709975 GPa |
| 200 mmH₂O | 0.00000196133 GPa |
| 250 mmH₂O | 0.0000024516625 GPa |
| 300 mmH₂O | 0.000002941995 GPa |
| 500 mmH₂O | 0.000004903325 GPa |
| 1000 mmH₂O | 0.00000980665 GPa |
| 2000 mmH₂O | 0.0000196133 GPa |
| 5000 mmH₂O | 0.00004903325 GPa |
| 10000 mmH₂O | 0.0000980665 GPa |
Where it's used
Millimeters of Water are used for fan static pressure and duct design in Asia and Europe, while gigapascals appear in young's modulus and shear modulus of metals, ceramics and composites. Both measure pressure, stress and differential pressure (force per unit area), so the conversion is a fixed factor.
Millimeter of Water to other pressure units
| Conversion | 1 mmH₂O equals |
|---|---|
| millimeter of water to gigapascal | 9.80665 × 10⁻⁹ GPa |
| millimeter of water to pascal | 9.80665 Pa |
| millimeter of water to kilopascal | 0.00980665 kPa |
| millimeter of water to ksi | 0.000001422334331 ksi |
| millimeter of water to kilogram-force per square centimetre | 0.0001 kgf/cm² |
| millimeter of water to psi | 0.001422334331 psi |
| millimeter of water to bar | 0.0000980665 bar |
| millimeter of water to millimeter of mercury | 0.07355591353 mmHg |
Show 12 more units
| millimeter of water to inch of water | 0.03937007874 inH₂O |
|---|---|
| millimeter of water to atmosphere | 0.00009678411054 atm |
| millimeter of water to megapascal | 0.00000980665 MPa |
| millimeter of water to newton per square millimetre | 0.00000980665 N/mm² |
| millimeter of water to kilogram-force per square millimetre | 0.000001 kgf/mm² |
| millimeter of water to millibar | 0.0980665 mbar |
| millimeter of water to torr | 0.07355592401 Torr |
| millimeter of water to centimeter of water | 0.1 cmH₂O |
| millimeter of water to inch of mercury | 0.002895902107 inHg |
| millimeter of water to decibar | 0.000980665 dbar |
| millimeter of water to inch of water (60 °F) | 0.03940945989 inH₂O (60 °F) |
| millimeter of water to barye | 98.0665 Ba |
Frequently asked questions
How many gigapascals are in 1 millimeter of water?
1 mmH₂O = 9.80665 × 10⁻⁹ GPa.
How do I convert millimeters of water to gigapascals?
Multiply the value in mmH₂O by 9.80665 × 10⁻⁹, or divide it by 101971621.3. For example, 15 mmH₂O × 9.80665 × 10⁻⁹ = 1.4709975 × 10⁻⁷ GPa.
Is the mmH₂O to GPa conversion exact?
Yes. Both units are defined exactly, and 1 mmH₂O is exactly 9.80665 × 10⁻⁹ GPa.
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, "millimeter of water, conventional (mmH2O)".
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 7, SI prefixes.
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Millimeters of Water to Gigapascals (mmH2O to GPa). Retrieved October 25, 2026, from https://scientificconverters.com/pressure/millimeter-of-water-to-gigapascal/
IEEE
Scientific Converters, "Convert Millimeters of Water to Gigapascals (mmH2O to GPa)," scientificconverters.com. Accessed: Oct. 25, 2026. [Online]. Available: https://scientificconverters.com/pressure/millimeter-of-water-to-gigapascal/