Zettagray is 1e+21 gray units.
Zettagrays to Petagrays Converter — ZGy to PGy
Convert Zettagray (ZGy) to Petagray (PGy) using the exact conversion factor (1 zettagray = 1,000,000 petagray). See the formula, worked examples, and conversion table.
Zettagrays 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 Zettagrays to Petagrays
Zettagray 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: Zettagray is 1e+21 gray units, and petagray is 1000000000000000 gray units.
Formula
petagrays = zettagrays × 1000000
This factor comes from each unit's defined relationship to the category's base unit: 1 zettagray equals 1e+21 base units, and 1 petagray equals 1e+15 base units, so dividing one by the other gives the direct zettagray-to-petagray factor of 1000000.
Simple example
1 ZGy × 1000000 = 1,000,000 PGy
1 zettagray = 1,000,000 petagrays.
Real-world example
10 ZGy × 1000000 = 10,000,000 PGy
10 zettagrays = 10,000,000 petagrays.
Conversion table
| Zettagray (ZGy) | Petagray (PGy) |
|---|---|
| 0.001 ZGy | 1,000 PGy |
| 0.01 ZGy | 10,000 PGy |
| 0.1 ZGy | 100,000 PGy |
| 1 ZGy | 1,000,000 PGy |
| 10 ZGy | 10,000,000 PGy |
| 100 ZGy | 100,000,000 PGy |
Reverse conversion: Petagray to Zettagray
1 PGy × 0.000001 = 0.000001 ZGy
1 petagray = 0.000001 zettagrays.
zettagrays = petagrays × 0.000001
For a page dedicated to this direction, see Petagray to Zettagray.
Understanding the Zettagray (ZGy)
Zettagray 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 zettagray?
1 zettagray equals 1,000,000 petagrays, using the exact defined conversion factor rather than an estimate.
How do I convert zettagray to petagray?
Multiply the zettagray value by 1000000. The converter above does this instantly to whatever precision you set.
How do I convert petagray back to zettagray?
Use the reverse factor: 1 petagray equals 0.000001 zettagrays. You can also use the swap control in the converter above to flip the direction instantly.
What is a zettagray?
Zettagray (ZGy) is a unit of radiation.
What is a petagray?
Petagray (PGy) is a unit of radiation.
Is the zettagray to petagray conversion exact?
Yes. Both zettagray and petagray are defined by fixed standards rather than physical artifacts, so the factor of 1000000 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.