Zeptopascal is 1e-21 pascal units.
Zeptopascals to Attopascals Converter — zPa to aPa
Convert Zeptopascal (zPa) to Attopascal (aPa) using the exact conversion factor (1 zeptopascal = 0.001 attopascal). See the formula, worked examples, and conversion table.
Zeptopascals to Attopascals converter
Converter
Pressure Converter
Convert pascals, bars, PSI, atmospheres, mercury columns, water columns, and engineering pressure units.
Context values
Some unit families need one extra value for a physically accurate result.
Attopascal is 1e-18 pascal units.
Result = input x 1e-21 / 1e-18.
Pressure uses the pascal as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Zeptopascals to Attopascals
Zeptopascal and Attopascal both show up on pressure gauges — psi is standard on US tire and tool specifications, while bar is the everyday pressure unit across most of the rest of the world. Specifically: Zeptopascal is 1e-21 pascal units, and attopascal is 1e-18 pascal units.
Formula
attopascals = zeptopascals × 0.001
This factor comes from each unit's defined relationship to the category's base unit: 1 zeptopascal equals 1e-21 base units, and 1 attopascal equals 1e-18 base units, so dividing one by the other gives the direct zeptopascal-to-attopascal factor of 0.001.
Simple example
1 zPa × 0.001 = 0.001 aPa
1 zeptopascal = 0.001 attopascals.
Real-world example
35 zPa × 0.001 = 0.035 aPa
35 zeptopascals = 0.035 attopascals.
Conversion table
| Zeptopascal (zPa) | Attopascal (aPa) |
|---|---|
| 1 zPa | 0.001 aPa |
| 5 zPa | 0.005 aPa |
| 10 zPa | 0.01 aPa |
| 25 zPa | 0.025 aPa |
| 50 zPa | 0.05 aPa |
| 100 zPa | 0.1 aPa |
Reverse conversion: Attopascal to Zeptopascal
0.001 aPa × 1000 = 1 zPa
0.001 attopascals = 1 zeptopascals.
zeptopascals = attopascals × 1000
For a page dedicated to this direction, see Attopascal to Zeptopascal.
Understanding the Zeptopascal (zPa)
Zeptopascal is 1e-21 pascal units.
Understanding the Attopascal (aPa)
Attopascal is 1e-18 pascal units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many attopascals are in 1 zeptopascal?
1 zeptopascal equals 0.001 attopascals, using the exact defined conversion factor rather than an estimate.
How do I convert zeptopascal to attopascal?
Multiply the zeptopascal value by 0.001. The converter above does this instantly to whatever precision you set.
How do I convert attopascal back to zeptopascal?
Use the reverse factor: 1 attopascal equals 1,000 zeptopascals. You can also use the swap control in the converter above to flip the direction instantly.
What is a zeptopascal?
Zeptopascal (zPa) is a unit of pressure.
What is a attopascal?
Attopascal (aPa) is a unit of pressure.
Is the zeptopascal to attopascal conversion exact?
Yes. Both zeptopascal and attopascal are defined by fixed standards rather than physical artifacts, so the factor of 0.001 used above is exact to as many digits as you choose to display.