Authoritative definitions of the International System of Units and SI prefixes.
Dedicated unit pair
Microsieverts to Millisieverts
Convert µSv to mSv instantly, then review the formula, assumptions, and rounding guidance.
Radiation unitsInstant result
Decimals
Formula result = input × 0.000001 ÷ 0.001. 1 µSv = 0.001 mSv
Common examples
One value, several units
Sieverts0 Sv
Millisieverts0.001 mSv
Rem0.0001 rem
Conversion table
| µSv | mSv |
|---|---|
| 1 µSv | 0.001 mSv |
| 2 µSv | 0.002 mSv |
| 5 µSv | 0.005 mSv |
| 10 µSv | 0.01 mSv |
| 25 µSv | 0.025 mSv |
| 50 µSv | 0.05 mSv |
| 100 µSv | 0.1 mSv |
Conversion chart
1 µSv0.001 mSv
5 µSv0.005 mSv
10 µSv0.01 mSv
25 µSv0.025 mSv
50 µSv0.05 mSv
Worked example
1 sievert equals 100 rem.
Unit definition
Microsieverts (µSv) One microsieverts equals 0.000001 sievert.
Unit history
Microsieverts is represented here using its modern SI definition or an internationally accepted relationship to an SI base unit.
Step by step
1. Parse the value, including fractions.
2. Convert µSv to sievert.
3. Convert the base value to mSv and apply your display precision.
Important
Equivalent dose already includes the applicable radiation weighting factor.
Understand the result before using it
Microsieverts to Millisieverts converts a value measured in Microsieverts (µSv) into the equivalent value in Millisieverts (mSv). The numerical value changes because the size and definition of the selected unit changes; the underlying quantity does not.
Calculated result
The conversion follows the displayed unit relationship. Display rounding can hide additional digits, and measured inputs cannot become more accurate merely by changing units.
Formula, assumptions, and example
Formula
result = input × 0.000001 ÷ 0.001
Assumptions
- Microsieverts and Millisieverts represent the same equivalent dose quantity.
- The input is expressed in µSv; the output is expressed in mSv.
- Equivalent dose already includes the applicable radiation weighting factor.
Worked example
1 µSv = 0.001 mSv. For another value, apply the same relationship and round only to the precision your source measurement supports.
When to use it
Good uses
- Read a µSv measurement in a document that expects mSv.
- Compare a microsieverts value with a value reported in millisieverts.
- Check the µSv-to-mSv arithmetic before copying the result into another calculation.
Limitations
Common mistakes to avoid
- Absorbed dose, equivalent dose, and activity describe different radiation quantities and are not interchangeable.
- Round the output to a precision justified by the original measurement.
- Verify safety-critical, regulated, laboratory, and contractual conversions against the controlling standard.
Sources and further reading
These references explain the underlying standards or provide authoritative context. Your own contract, institution, clinician, product documentation, local code, or governing standard may be the controlling source.
Guidance on unit names, symbols, conversions, and numerical presentation.
Questions about this calculation
How do I convert Microsieverts to Millisieverts?
result = input × 0.000001 ÷ 0.001 Using the displayed relationship, 1 µSv equals 0.001 mSv.
How many Millisieverts are in one Microsieverts?
One Microsieverts is 0.001 Millisieverts. The displayed digits may be rounded.
Can I reverse the µSv to mSv conversion?
Yes. Swap the source and target units in the converter. The reverse relationship converts mSv back to µSv.
Is the Microsieverts to Millisieverts result exact?
The conversion follows the displayed unit relationship. Display rounding can hide additional digits, and measured inputs cannot become more accurate merely by changing units.