Unit converter

Radiation dose.

Convert mSv to rem, or pick any of the 5 units in the menus. Type in either box and the other follows. Equivalent dose, weighted for biological effect. The gray measures absorbed energy and is a different quantity, deliberately kept off this page.

mSv → remExact definition
Millisieverts to rems — common values, to 6 significant figures.
mSvrem
1 mSv0.1 rem
2 mSv0.2 rem
3 mSv0.3 rem
4 mSv0.4 rem
5 mSv0.5 rem
10 mSv1 rem
15 mSv1.5 rem
20 mSv2 rem
25 mSv2.5 rem
50 mSv5 rem
75 mSv7.5 rem
100 mSv10 rem
250 mSv25 rem
500 mSv50 rem
1000 mSv100 rem
1 mSv=0.1 rem 1 rem=10 mSv

Definitions

  • The millisievert measures equivalent dose — absorbed energy weighted for biological harm. UK natural background is about 2.7 mSv a year.
  • The rem is the older US unit, exactly 0.01 Sv. A chest X-ray is roughly 0.01 rem.
  • The sievert measures equivalent or effective dose. The gray measures absorbed dose; they are different physical quantities and are not mixed here.
  • Every unit in the menus is exact by definition, so the only rounding on this page is the one you choose for the display.

How it works

Every value is converted into sieverts and then back out into the unit you asked for. One route covers every pairing in the menus, so an unusual combination is no less accurate than a common one, and adding a unit affects only that unit.

Both boxes are live. Whichever one you last typed in is the source, changing either menu recalculates straight away, and Swap exchanges the units and the values so the number you are reading stays where you are looking.

Display precision sets a maximum number of significant figures and trims trailing zeroes, so it changes what you see and never what was calculated. The editable box always holds a plain number at full working precision, so you can carry on from either side.

Common questions this answers: how many rems in a millisievert (0.1), how many millisieverts in a rem (10), and what 1 mSv is in rems (0.1 rem).