Hectogray is 100 gray units.
Hectograys to Attograys Converter — hGy to aGy
Convert Hectogray (hGy) to Attogray (aGy) using the exact conversion factor (1 hectogray = 1e+20 attogray). See the formula, worked examples, and conversion table.
Hectograys to Attograys 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.
Attogray is 1e-18 gray units.
Result = input x 100 / 1e-18.
Absorbed Dose units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Hectograys to Attograys
Hectogray and Attogray 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: Hectogray is 100 gray units, and attogray is 1e-18 gray units.
Formula
attograys = hectograys × 1e+20
This factor comes from each unit's defined relationship to the category's base unit: 1 hectogray equals 100 base units, and 1 attogray equals 1e-18 base units, so dividing one by the other gives the direct hectogray-to-attogray factor of 1e+20.
Simple example
1 hGy × 1e+20 = 1e+20 aGy
1 hectogray = 1e+20 attograys.
Real-world example
10 hGy × 1e+20 = 1e+21 aGy
10 hectograys = 1e+21 attograys.
Conversion table
| Hectogray (hGy) | Attogray (aGy) |
|---|---|
| 0.001 hGy | 1e+17 aGy |
| 0.01 hGy | 1e+18 aGy |
| 0.1 hGy | 1e+19 aGy |
| 1 hGy | 1e+20 aGy |
| 10 hGy | 1e+21 aGy |
| 100 hGy | 1e+22 aGy |
Reverse conversion: Attogray to Hectogray
1e+20 aGy × 1e-20 = 1 hGy
1e+20 attograys = 1 hectograys.
hectograys = attograys × 1e-20
For a page dedicated to this direction, see Attogray to Hectogray.
Understanding the Hectogray (hGy)
Hectogray is 100 gray units.
Understanding the Attogray (aGy)
Attogray is 1e-18 gray units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many attograys are in 1 hectogray?
1 hectogray equals 1e+20 attograys, using the exact defined conversion factor rather than an estimate.
How do I convert hectogray to attogray?
Multiply the hectogray value by 1e+20. The converter above does this instantly to whatever precision you set.
How do I convert attogray back to hectogray?
Use the reverse factor: 1 attogray equals 1e-20 hectograys. You can also use the swap control in the converter above to flip the direction instantly.
What is a hectogray?
Hectogray (hGy) is a unit of radiation.
What is a attogray?
Attogray (aGy) is a unit of radiation.
Is the hectogray to attogray conversion exact?
Yes. Both hectogray and attogray are defined by fixed standards rather than physical artifacts, so the factor of 1e+20 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.