Convert Millimeters of Water to Pascals
1 millimeter of water (mmH₂O) equals 9.80665 pascals (Pa).
1 mmH₂O = 9.80665 Pa
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk millimeter of water to pascal converter to paste a column from Excel.
How to Convert Millimeter of Water to Pascal
- 1 mmH₂O = 9.80665 Pa
- 1 Pa = 0.1019716213 mmH₂O
- Example: convert 15 mmH₂O to Pa: 15 mmH₂O = 15 × 9.80665 Pa = 147.09975 Pa
Reference conditions. mmH₂O: Conventional water column: ρ = 1000 kg/m³ and gₙ = 9.80665 m/s² (≈ water at 4 °C).
Formula
Pa = mmH₂O × 9.80665
Derivation from SI units:
- 1 mmH₂O = 1000 kg/m³ × 9.80665 m/s² × 0.001 m = 9.80665 Pa
- 1 Pa = 1 N/m² = 1 kg·m⁻¹·s⁻²
Both units are defined exactly, so the factor is exact. Millimeter of Water definition: millimeter of water; Pascal definition: pascal.
Worked examples
- A fan rated at 25 mmH₂O static pressure delivers 245.16625 Pa.
25 mmH₂O × 9.80665 = 245.16625 Pa - An HVAC filter with a 150 mmH₂O final resistance is at 1470.9975 Pa.
150 mmH₂O × 9.80665 = 1470.9975 Pa
Millimeter of Water to Pascal conversion table
| Millimeters of Water (mmH₂O) | Pascals (Pa) |
|---|---|
| 1 mmH₂O | 9.80665 Pa |
| 2 mmH₂O | 19.6133 Pa |
| 5 mmH₂O | 49.03325 Pa |
| 10 mmH₂O | 98.0665 Pa |
| 15 mmH₂O | 147.09975 Pa |
| 20 mmH₂O | 196.133 Pa |
| 25 mmH₂O | 245.16625 Pa |
| 30 mmH₂O | 294.1995 Pa |
| 50 mmH₂O | 490.3325 Pa |
| 75 mmH₂O | 735.49875 Pa |
| 100 mmH₂O | 980.665 Pa |
| 150 mmH₂O | 1470.9975 Pa |
| 200 mmH₂O | 1961.33 Pa |
| 250 mmH₂O | 2451.6625 Pa |
| 300 mmH₂O | 2941.995 Pa |
| 500 mmH₂O | 4903.325 Pa |
| 1000 mmH₂O | 9806.65 Pa |
| 2000 mmH₂O | 19613.3 Pa |
| 5000 mmH₂O | 49033.25 Pa |
| 10000 mmH₂O | 98066.5 Pa |
Where it's used
Asian fan curves and filter tables in mmAq are converted to pascals for ISO 16890 comparisons, energy calculations and SI-based building controls.
Millimeter of Water to other pressure units
| Conversion | 1 mmH₂O equals |
|---|---|
| millimeter of water to pascal | 9.80665 Pa |
| millimeter of water to kilopascal | 0.00980665 kPa |
| millimeter of water to megapascal | 0.00000980665 MPa |
| millimeter of water to psi | 0.001422334331 psi |
| millimeter of water to bar | 0.0000980665 bar |
| millimeter of water to millibar | 0.0980665 mbar |
| millimeter of water to decibar | 0.000980665 dbar |
| millimeter of water to torr | 0.07355592401 Torr |
| millimeter of water to millimeter of mercury | 0.07355591353 mmHg |
| millimeter of water to centimeter of water | 0.1 cmH₂O |
| millimeter of water to inch of water | 0.03937007874 inH₂O |
| millimeter of water to inch of water (60 °F) | 0.03940945989 inH₂O (60 °F) |
| millimeter of water to inch of mercury | 0.002895902107 inHg |
| millimeter of water to atmosphere | 0.00009678411054 atm |
| millimeter of water to barye | 98.0665 Ba |
Frequently asked questions
What does mmAq mean?
mmAq (millimetres of aqua) is another name for mmH₂O, millimetres of water column. 1 mmAq = 9.80665 Pa.
How many pascals are in 1 millimeter of water?
1 mmH₂O = 9.80665 Pa.
How do I convert millimeters of water to pascals?
Multiply the value in mmH₂O by 9.80665. For example, 15 mmH₂O × 9.80665 = 147.09975 Pa.
Is the mmH₂O to Pa conversion exact?
Yes. Both units are defined exactly, and 1 mmH₂O is exactly 9.80665 Pa.
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 4, coherent derived units with special names.
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 Pascals. Retrieved October 17, 2026, from https://scientificconverters.com/pressure/millimeter-of-water-to-pascal/
IEEE
Scientific Converters, "Convert Millimeters of Water to Pascals," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/pressure/millimeter-of-water-to-pascal/