Convert Kilopascals to Millimeters of Water
1 kilopascal (kPa) equals 101.9716213 millimeters of water (mmH₂O).
1 kPa = 101.9716213 mmH₂O
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk kilopascal to millimeter of water converter to paste a column from Excel.
How to Convert Kilopascal to Millimeter of Water
- 1 kPa = 101.9716213 mmH₂O
- 1 mmH₂O = 0.00980665 kPa
- Example: convert 15 kPa to mmH₂O: 15 kPa = 15 × 101.9716213 mmH₂O = 1529.574319 mmH₂O
Reference conditions. mmH₂O: Conventional water column: ρ = 1000 kg/m³ and gₙ = 9.80665 m/s² (≈ water at 4 °C).
Formula
mmH₂O = kPa × 101.9716212978
Derivation from SI units:
- 1 kPa = 10³ Pa
- 1 mmH₂O = 1000 kg/m³ × 9.80665 m/s² × 0.001 m = 9.80665 Pa
- 1 kPa = 1000 Pa ÷ 9.80665 Pa per mmH₂O = 101.9716212978 mmH₂O
Both units are defined exactly, so the factor is exact. Kilopascal definition: kilopascal; Millimeter of Water definition: millimeter of water.
Worked examples
- A reading of 20 kPa converts to 2039.432426 mmH₂O.
20 kPa × 101.9716213 = 2039.432426 mmH₂O - A value of 300 kPa is 30591.48639 mmH₂O.
300 kPa × 101.9716213 = 30591.48639 mmH₂O
Kilopascal to Millimeter of Water conversion table
| Kilopascals (kPa) | Millimeters of Water (mmH₂O) |
|---|---|
| 0.1 kPa | 10.19716213 mmH₂O |
| 0.25 kPa | 25.49290532 mmH₂O |
| 0.5 kPa | 50.98581065 mmH₂O |
| 1 kPa | 101.9716213 mmH₂O |
| 2 kPa | 203.9432426 mmH₂O |
| 2.5 kPa | 254.9290532 mmH₂O |
| 5 kPa | 509.8581065 mmH₂O |
| 10 kPa | 1019.716213 mmH₂O |
| 20 kPa | 2039.432426 mmH₂O |
| 50 kPa | 5098.581065 mmH₂O |
| 100 kPa | 10197.16213 mmH₂O |
| 101.325 kPa | 10332.27453 mmH₂O |
| 150 kPa | 15295.74319 mmH₂O |
| 200 kPa | 20394.32426 mmH₂O |
| 220 kPa | 22433.75669 mmH₂O |
| 250 kPa | 25492.90532 mmH₂O |
| 300 kPa | 30591.48639 mmH₂O |
| 350 kPa | 35690.06745 mmH₂O |
| 400 kPa | 40788.64852 mmH₂O |
| 500 kPa | 50985.81065 mmH₂O |
| 600 kPa | 61182.97278 mmH₂O |
| 700 kPa | 71380.13491 mmH₂O |
| 800 kPa | 81577.29704 mmH₂O |
| 1000 kPa | 101971.6213 mmH₂O |
| 2000 kPa | 203943.2426 mmH₂O |
Where it's used
Kilopascals are used for tyre pressure outside the United States (about 200–250 kPa for cars), while millimeters of water appear in fan static pressure and duct design in Asia and Europe. Both measure pressure, stress and differential pressure (force per unit area), so the conversion is a fixed factor.
Kilopascal to other pressure units
| Conversion | 1 kPa equals |
|---|---|
| kilopascal to pascal | 1000 Pa |
| kilopascal to megapascal | 0.001 MPa |
| kilopascal to psi | 0.1450377377 psi |
| kilopascal to bar | 0.01 bar |
| kilopascal to millibar | 10 mbar |
| kilopascal to decibar | 0.1 dbar |
| kilopascal to torr | 7.500616827 Torr |
| kilopascal to millimeter of mercury | 7.500615758 mmHg |
| kilopascal to millimeter of water | 101.9716213 mmH₂O |
| kilopascal to centimeter of water | 10.19716213 cmH₂O |
| kilopascal to inch of water | 4.01463076 inH₂O |
| kilopascal to inch of water (60 °F) | 4.01864652 inH₂O (60 °F) |
| kilopascal to inch of mercury | 0.295299833 inHg |
| kilopascal to atmosphere | 0.009869232667 atm |
| kilopascal to barye | 10000 Ba |
Frequently asked questions
How many millimeters of water are in 1 kilopascal?
1 kPa = 101.9716213 mmH₂O.
How do I convert kilopascals to millimeters of water?
Multiply the value in kPa by 101.9716213. For example, 15 kPa × 101.9716213 = 1529.574319 mmH₂O.
Is the kPa to mmH₂O conversion exact?
Yes. Both units are defined exactly, so the ratio is exact; its decimal form does not terminate and is shown here to 10 significant figures (more with the precision selector).
Sources
- The International System of Units (SI), 9th edition (SI Brochure), Bureau International des Poids et Mesures , Table 7, SI prefixes.
- 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)".
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 Kilopascals to Millimeters of Water. Retrieved October 17, 2026, from https://scientificconverters.com/pressure/kilopascal-to-millimeter-of-water/
IEEE
Scientific Converters, "Convert Kilopascals to Millimeters of Water," scientificconverters.com. Accessed: Oct. 17, 2026. [Online]. Available: https://scientificconverters.com/pressure/kilopascal-to-millimeter-of-water/