Megagray is 1000000 gray units.
Megagrays to Petagrays Converter — MGy to PGy
Convert Megagray (MGy) to Petagray (PGy) using the exact conversion factor (1 megagray = 1e-9 petagray). See the formula, worked examples, and conversion table.
Megagrays 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+6 / 1e+15.
Absorbed Dose units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Megagrays to Petagrays
Megagray 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: Megagray is 1000000 gray units, and petagray is 1000000000000000 gray units.
Formula
petagrays = megagrays × 1e-9
This factor comes from each unit's defined relationship to the category's base unit: 1 megagray equals 1000000 base units, and 1 petagray equals 1e+15 base units, so dividing one by the other gives the direct megagray-to-petagray factor of 1e-9.
Simple example
1 MGy × 1e-9 = 1e-9 PGy
1 megagray = 1e-9 petagrays.
Real-world example
10 MGy × 1e-9 = 1e-8 PGy
10 megagrays = 1e-8 petagrays.
Conversion table
| Megagray (MGy) | Petagray (PGy) |
|---|---|
| 0.001 MGy | 1e-12 PGy |
| 0.01 MGy | 1e-11 PGy |
| 0.1 MGy | 1e-10 PGy |
| 1 MGy | 1e-9 PGy |
| 10 MGy | 1e-8 PGy |
| 100 MGy | 1e-7 PGy |
Reverse conversion: Petagray to Megagray
1e-9 PGy × 1000000000 = 1 MGy
1e-9 petagrays = 1 megagrays.
megagrays = petagrays × 1000000000
For a page dedicated to this direction, see Petagray to Megagray.
Understanding the Megagray (MGy)
Megagray is 1000000 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 megagray?
1 megagray equals 1e-9 petagrays, using the exact defined conversion factor rather than an estimate.
How do I convert megagray to petagray?
Multiply the megagray value by 1e-9. The converter above does this instantly to whatever precision you set.
How do I convert petagray back to megagray?
Use the reverse factor: 1 petagray equals 1,000,000,000 megagrays. You can also use the swap control in the converter above to flip the direction instantly.
What is a megagray?
Megagray (MGy) is a unit of radiation.
What is a petagray?
Petagray (PGy) is a unit of radiation.
Is the megagray to petagray conversion exact?
Yes. Both megagray and petagray are defined by fixed standards rather than physical artifacts, so the factor of 1e-9 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.