Sievert is equivalent dose.
Sieverts to Megasieverts Converter — Sv to MSv
Convert Sievert (Sv) to Megasievert (MSv) using the exact conversion factor (1 sievert = 0.000001 megasievert). See the formula, worked examples, conversion table, history, and common uses.
Sieverts to Megasieverts 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.
Megasievert is 1000000 sievert units.
Result = input x 1 / 1e+6.
Equivalent Dose units are compatible.
Reserved above the conversion cards and below the converter.
About Converting Sieverts to Megasieverts
Sievert and Megasievert 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. Sievert is most often used for radiation safety dose limits for workers and the public.
Formula
megasieverts = sieverts × 0.000001
This factor comes from each unit's defined relationship to the category's base unit: 1 sievert equals 1 base unit, and 1 megasievert equals 1000000 base units, so dividing one by the other gives the direct sievert-to-megasievert factor of 0.000001.
Simple example
1 Sv × 0.000001 = 0.000001 MSv
1 sievert = 0.000001 megasieverts.
Real-world example
10 Sv × 0.000001 = 0.00001 MSv
10 sieverts = 0.00001 megasieverts.
Conversion table
| Sievert (Sv) | Megasievert (MSv) |
|---|---|
| 0.001 Sv | 1e-9 MSv |
| 0.01 Sv | 1e-8 MSv |
| 0.1 Sv | 1e-7 MSv |
| 1 Sv | 0.000001 MSv |
| 10 Sv | 0.00001 MSv |
| 100 Sv | 0.0001 MSv |
Reverse conversion: Megasievert to Sievert
0.000001 MSv × 1000000 = 1 Sv
0.000001 megasieverts = 1 sievert.
sieverts = megasieverts × 1000000
For a page dedicated to this direction, see Megasievert to Sievert.
Understanding the Sievert
Sievert (Sv) measures equivalent radiation dose. The SI derived unit of equivalent radiation dose, weighting the physically absorbed dose (in gray) for how biologically damaging the specific type of radiation is. It is classified as a SI derived unit.
Where it's used: Universal — SI derived unit used worldwide in radiation protection
Sievert vs. gray. The gray measures physically absorbed radiation energy; the sievert adjusts that figure for biological harm, since equal absorbed doses of different radiation types (e.g. alpha particles vs. X-rays) can cause very different amounts of damage.
Uses of the Sievert today
- Radiation safety dose limits for workers and the public
- Medical imaging (CT scan, X-ray) dose reporting
- Background and environmental radiation exposure reporting
History of the Sievert
The sievert is named after Rolf Sievert (1896–1966), a Swedish medical physicist whose research on radiation measurement and safety standards was foundational to modern radiation protection practice; the unit was adopted by the CGPM in 1977.
Historical origin. Sievert was not the invention of a single named person; it developed through the process described above.
Understanding the Megasievert (MSv)
Megasievert is 1000000 sievert units.
Sievert — sources
- BIPM SI Brochure, 9th edition — Official definition of the sievert as an SI derived unit.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many megasieverts are in 1 sievert?
1 sievert equals 0.000001 megasieverts, using the exact defined conversion factor rather than an estimate.
How do I convert sievert to megasievert?
Multiply the sievert value by 0.000001. The converter above does this instantly to whatever precision you set.
How do I convert megasievert back to sievert?
Use the reverse factor: 1 megasievert equals 1,000,000 sieverts. You can also use the swap control in the converter above to flip the direction instantly.
What is a sievert?
Sievert (Sv) measures equivalent radiation dose. The SI derived unit of equivalent radiation dose, weighting the physically absorbed dose (in gray) for how biologically damaging the specific type of radiation is. It is classified as a SI derived unit.
What is a megasievert?
Megasievert (MSv) is a unit of radiation.
Is the sievert to megasievert conversion exact?
Yes. Both sievert and megasievert are defined by fixed standards rather than physical artifacts, so the factor of 0.000001 used above is exact to as many digits as you choose to display.
What is the difference between sievert vs. gray?
The gray measures physically absorbed radiation energy; the sievert adjusts that figure for biological harm, since equal absorbed doses of different radiation types (e.g. alpha particles vs. X-rays) can cause very different amounts of damage.
Where is the sievert still used today?
Universal — SI derived unit used worldwide in radiation protection