Gigasievert is 1000000000 sievert units.
Gigasieverts to Millisieverts Converter — GSv to mSv
Convert Gigasievert (GSv) to Millisievert (mSv) using the exact conversion factor (1 gigasievert = 1e+12 millisievert). See the formula, worked examples, and conversion table.
Gigasieverts to Millisieverts 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.
Millisievert is 0.001 sievert units.
Result = input x 1e+9 / 0.001.
Equivalent Dose units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Gigasieverts to Millisieverts
Gigasievert and Millisievert 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: Gigasievert is 1000000000 sievert units, and millisievert is 0.001 sievert units.
Formula
millisieverts = gigasieverts × 1e+12
This factor comes from each unit's defined relationship to the category's base unit: 1 gigasievert equals 1000000000 base units, and 1 millisievert equals 0.001 base units, so dividing one by the other gives the direct gigasievert-to-millisievert factor of 1e+12.
Simple example
1 GSv × 1e+12 = 1e+12 mSv
1 gigasievert = 1e+12 millisieverts.
Real-world example
10 GSv × 1e+12 = 1e+13 mSv
10 gigasieverts = 1e+13 millisieverts.
Conversion table
| Gigasievert (GSv) | Millisievert (mSv) |
|---|---|
| 0.001 GSv | 1,000,000,000 mSv |
| 0.01 GSv | 10,000,000,000 mSv |
| 0.1 GSv | 100,000,000,000 mSv |
| 1 GSv | 1e+12 mSv |
| 10 GSv | 1e+13 mSv |
| 100 GSv | 1e+14 mSv |
Reverse conversion: Millisievert to Gigasievert
1e+12 mSv × 1e-12 = 1 GSv
1e+12 millisieverts = 1 gigasievert.
gigasieverts = millisieverts × 1e-12
For a page dedicated to this direction, see Millisievert to Gigasievert.
Understanding the Gigasievert (GSv)
Gigasievert is 1000000000 sievert units.
Understanding the Millisievert (mSv)
Millisievert is 0.001 sievert units.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many millisieverts are in 1 gigasievert?
1 gigasievert equals 1e+12 millisieverts, using the exact defined conversion factor rather than an estimate.
How do I convert gigasievert to millisievert?
Multiply the gigasievert value by 1e+12. The converter above does this instantly to whatever precision you set.
How do I convert millisievert back to gigasievert?
Use the reverse factor: 1 millisievert equals 1e-12 gigasieverts. You can also use the swap control in the converter above to flip the direction instantly.
What is a gigasievert?
Gigasievert (GSv) is a unit of radiation.
What is a millisievert?
Millisievert (mSv) is a unit of radiation.
Is the gigasievert to millisievert conversion exact?
Yes. Both gigasievert and millisievert are defined by fixed standards rather than physical artifacts, so the factor of 1e+12 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.