Zeptogray is 1e-21 gray units.
Zeptograys to Petagrays Converter — zGy to PGy
Convert Zeptogray (zGy) to Petagray (PGy) using the exact conversion factor (1 zeptogray = 1e-36 petagray). See the formula, worked examples, and conversion table.
Zeptograys to Petagrays converter
Converter
Radiation Converter
Convert radioactivity, absorbed dose, and equivalent dose units by compatible radiation family.
Context values
Some unit families need one extra value for a physically accurate result.
Petagray is 1000000000000000 gray units.
Result = input x 1e-21 / 1e+15.
Absorbed Dose units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Zeptograys to Petagrays
Zeptogray and Petagray both belong to the radiation-measurement family, though radiation quantities fall into genuinely distinct categories: absorbed dose (gray, rad) measures energy deposited in matter, equivalent dose (sievert, rem) weights that for biological harm, and activity (becquerel, curie) measures how often a radioactive source decays — this page only converts between units of the same kind. Specifically: Zeptogray is 1e-21 gray units, and petagray is 1000000000000000 gray units.
Formula
petagrays = zeptograys × 1e-36
This factor comes from each unit's defined relationship to the category's base unit: 1 zeptogray equals 1e-21 base units, and 1 petagray equals 1e+15 base units, so dividing one by the other gives the direct zeptogray-to-petagray factor of 1e-36.
Simple example
1 zGy × 1e-36 = 1e-36 PGy
1 zeptogray = 1e-36 petagrays.
Real-world example
10 zGy × 1e-36 = 1e-35 PGy
10 zeptograys = 1e-35 petagrays.
Conversion table
| Zeptogray (zGy) | Petagray (PGy) |
|---|---|
| 0.001 zGy | 1e-39 PGy |
| 0.01 zGy | 1e-38 PGy |
| 0.1 zGy | 1e-37 PGy |
| 1 zGy | 1e-36 PGy |
| 10 zGy | 1e-35 PGy |
| 100 zGy | 1e-34 PGy |
Reverse conversion: Petagray to Zeptogray
1e-36 PGy × 1e+36 = 1 zGy
1e-36 petagrays = 1 zeptogray.
zeptograys = petagrays × 1e+36
For a page dedicated to this direction, see Petagray to Zeptogray.
Understanding the Zeptogray (zGy)
Zeptogray is 1e-21 gray units.
Understanding the Petagray (PGy)
Petagray is 1000000000000000 gray units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many petagrays are in 1 zeptogray?
1 zeptogray equals 1e-36 petagrays, using the exact defined conversion factor rather than an estimate.
How do I convert zeptogray to petagray?
Multiply the zeptogray value by 1e-36. The converter above does this instantly to whatever precision you set.
How do I convert petagray back to zeptogray?
Use the reverse factor: 1 petagray equals 1e+36 zeptograys. You can also use the swap control in the converter above to flip the direction instantly.
What is a zeptogray?
Zeptogray (zGy) is a unit of radiation.
What is a petagray?
Petagray (PGy) is a unit of radiation.
Is the zeptogray to petagray conversion exact?
Yes. Both zeptogray and petagray are defined by fixed standards rather than physical artifacts, so the factor of 1e-36 used above is exact to as many digits as you choose to display.
What's the difference between absorbed dose, equivalent dose, and activity?
Absorbed dose (gray, rad) measures the energy radiation deposits in matter. Equivalent dose (sievert, rem) adjusts that figure for how harmful different types of radiation are to biological tissue. Activity (becquerel, curie) measures how often a radioactive source decays, independent of how much dose a person actually receives from it.