mmH2O (4°C) to Atmosphere (std) Converter
Convert mmH2O (4°C) (mmH2O) to Atmosphere (std) (atm) instantly. 1 mmH2O = 9.678411e-5 atm.
Pressure Converter
29 units available
1 mmH2O = 9.678411e-5 atm
Formula:
atm = mmH2O × 0.0000967841With your value: 1 mmH2O = 9.678411e-5 atm
Other mmH2O (4°C) to Atmosphere (std) conversions
mmH2O (4°C) to Atmosphere (std) Conversion Table
| mmH2O (4°C) (mmH2O) | Atmosphere (std) (atm) |
|---|---|
| 0.5 | 4.839206e-5 |
| 1 | 9.678411e-5 |
| 2 | 0.000194 |
| 5 | 0.000484 |
| 10 | 0.000968 |
| 15 | 0.001452 |
| 20 | 0.001936 |
| 25 | 0.00242 |
| 50 | 0.004839 |
| 100 | 0.009678 |
| 250 | 0.024196 |
| 500 | 0.048392 |
| 1000 | 0.096784 |
Atmosphere (std) to mmH2O (4°C) Conversion Table
| Atmosphere (std) (atm) | mmH2O (4°C) (mmH2O) |
|---|---|
| 0.5 | 5,166.137264 |
| 1 | 10,332.274528 |
| 2 | 20,664.549056 |
| 5 | 51,661.37264 |
| 10 | 103,322.74528 |
| 15 | 154,984.11792 |
| 20 | 206,645.49056 |
| 25 | 258,306.8632 |
| 50 | 516,613.7264 |
| 100 | 1,033,227.4528 |
| 250 | 2,583,068.632 |
| 500 | 5,166,137.263999 |
| 1000 | 10,332,274.527999 |
Where these values come from
Every factor on this page is traced to the document that defines it. See the full provenance dataset or our methodology.
mmH2O (4°C) (mmH2O)
Pressure
Derived from the pascal (1 Pa = 1 N/m²). The standard atmosphere is exactly 101 325 Pa.
Source: NIST Special Publication 811, Guide for the Use of the International System of Units
National Institute of Standards and Technology (US) · Reviewed 2026-07-01
Atmosphere (std) (atm)
Pressure
The standard atmosphere is exactly 101 325 Pa.
Source: Units accepted for use with the SI, SI Brochure Table 8
Bureau International des Poids et Mesures · Reviewed 2026-07-01
How to Convert mmH2O (4°C) to Atmosphere (std)
To convert from mmH2O (4°C) (mmH2O) to Atmosphere (std) (atm), multiply the value by 9.678411e-5.
Formula: atm = mmH2O × 0.0000967841
Reverse: mmH2O = atm × 10,332.2745279989
Step-by-Step Example
- Start with your value in mmH2O (4°C). For example: 5 mmH2O
- Multiply by the conversion factor: 5 x 9.678411e-5
- The result is: 0.000484 atm
About mmH2O (4°C)
The mmh2o (4°c) (mmH2O) is a unit of pressure and stress. One mmh2o (4°c) equals 9.80665 pascals. UnitConvertLab converts it against every other pressure unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.
Common uses: pressure calculations, engineering and science, education.
About Atmosphere (std)
One standard atmosphere equals 101,325 Pascals and represents the average air pressure at sea level.
Common uses: diving, weather, chemistry.
Frequently Asked Questions
How many Atmosphere (std) are in 1 mmH2O (4°C)?
There are exactly 9.678411e-5 Atmosphere (std) in 1 mmH2O (4°C). This means the conversion factor from mmH2O (4°C) to Atmosphere (std) is 9.678411e-5.
What is the formula to convert mmH2O (4°C) to Atmosphere (std)?
The formula to convert mmH2O (4°C) to Atmosphere (std) is: atm = mmH2O × 0.0000967841. For example, to convert 10 mmH2O (4°C) to Atmosphere (std), you would multiply 10 by 9.678411e-5.
What is a mmH2O (4°C)?
The mmh2o (4°c) (mmH2O) is a unit of pressure and stress. One mmh2o (4°c) equals 9.80665 pascals. UnitConvertLab converts it against every other pressure unit using this exact definition, so results are reproducible to full double precision rather than rounded lookup tables.
What is a Atmosphere (std)?
One standard atmosphere equals 101,325 Pascals and represents the average air pressure at sea level.
What are the common uses of mmH2O (4°C)?
The mmH2O (4°C) is commonly used in pressure calculations, engineering and science, education.
Related Pressure Conversions
Cite this page
UnitConvertLab. (2026). mmH2O (4°C) to Atmosphere (std) converter. UnitConvertLab. Retrieved from https://unitconvertlab.com/convert/mmh2o-to-atmosphere