inch of water at 4°C to attopascal
Convert inch of water at 4°C (inH₂O) to attopascal (aPa). Use an editable pressure converter, conversion formula, and reference table.
1 inH₂O = 2.4908891e+20 aPa
Conversion formula
One inch of water at 4°C equals 2.4908891e+20 attopascal. Multiply your value in inch of water at 4°C by this factor to get attopascal. For the reverse conversion, divide by the same factor.
Worked example
To convert 5 inch of water at 4°C:5 × 2.4908891e+20 = 1.24544455e+21 aPa
Conversion table
| inch of water at 4°C (inH₂O) | attopascal (aPa) |
|---|---|
| 0.01 | 2.4908891e+18 |
| 0.1 | 2.4908891e+19 |
| 1 | 2.4908891e+20 |
| 2 | 4.9817782e+20 |
| 5 | 1.24544455e+21 |
| 10 | 2.4908891e+21 |
| 25 | 6.22722275e+21 |
| 50 | 1.24544455e+22 |
| 100 | 2.4908891e+22 |
| 1000 | 2.4908891e+23 |
About these measurements
Pressure is force per unit of area.
The base reference used here is the pascal. One inch of water at 4°C is 249.08891 base units; one attopascal is 1e-18 base units.
Important distinctions
Gauge and absolute pressures must not be mixed. This converts units without changing the reference pressure.
Precision
The converter uses stored conversion factors and floating-point arithmetic. Results display up to ten significant digits, switching to scientific notation for very small or large values. Keep the precision of your original measurement when reporting results.
Common questions
How do I convert inH₂O to aPa?
Multiply the quantity in inH₂O by 2.4908891e+20. You can also type the value into the converter above.
Can I reverse the conversion?
Yes. Use the swap button or open the attopascal to inch of water at 4°C converter.
Reference
NIST Guide to the SI — conversion factors and prefix conventions. SI prefixes scale units by powers of ten; the dimension-specific notes above describe the assumptions used on this page.
