Petagray is 1000000000000000 gray units.
Petagrays to Milligrays Converter — PGy to mGy
Convert Petagray (PGy) to Milligray (mGy) using the exact conversion factor (1 petagray = 1e+18 milligray). See the formula, worked examples, and conversion table.
Petagrays to Milligrays 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.
Milligray is 0.001 gray units.
Result = input x 1e+15 / 0.001.
Absorbed Dose units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Petagrays to Milligrays
Petagray and Milligray 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: Petagray is 1000000000000000 gray units, and milligray is 0.001 gray units.
Formula
milligrays = petagrays × 1e+18
This factor comes from each unit's defined relationship to the category's base unit: 1 petagray equals 1e+15 base units, and 1 milligray equals 0.001 base units, so dividing one by the other gives the direct petagray-to-milligray factor of 1e+18.
Simple example
1 PGy × 1e+18 = 1e+18 mGy
1 petagray = 1e+18 milligrays.
Real-world example
10 PGy × 1e+18 = 1e+19 mGy
10 petagrays = 1e+19 milligrays.
Conversion table
| Petagray (PGy) | Milligray (mGy) |
|---|---|
| 0.001 PGy | 1e+15 mGy |
| 0.01 PGy | 1e+16 mGy |
| 0.1 PGy | 1e+17 mGy |
| 1 PGy | 1e+18 mGy |
| 10 PGy | 1e+19 mGy |
| 100 PGy | 1e+20 mGy |
Reverse conversion: Milligray to Petagray
1e+18 mGy × 1e-18 = 1 PGy
1e+18 milligrays = 1 petagray.
petagrays = milligrays × 1e-18
For a page dedicated to this direction, see Milligray to Petagray.
Understanding the Petagray (PGy)
Petagray is 1000000000000000 gray units.
Understanding the Milligray (mGy)
Milligray is 0.001 gray units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many milligrays are in 1 petagray?
1 petagray equals 1e+18 milligrays, using the exact defined conversion factor rather than an estimate.
How do I convert petagray to milligray?
Multiply the petagray value by 1e+18. The converter above does this instantly to whatever precision you set.
How do I convert milligray back to petagray?
Use the reverse factor: 1 milligray equals 1e-18 petagrays. You can also use the swap control in the converter above to flip the direction instantly.
What is a petagray?
Petagray (PGy) is a unit of radiation.
What is a milligray?
Milligray (mGy) is a unit of radiation.
Is the petagray to milligray conversion exact?
Yes. Both petagray and milligray are defined by fixed standards rather than physical artifacts, so the factor of 1e+18 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.