Equivalent Dose Converter

What the Equivalent Dose Converter does

Equivalent Dose Converter: 1 Sv = 100 rem, so multiply a sievert value by 100 to get rem, or divide to go back. Example: 1 Sv = 100 rem.

Feed it Value, From and To; it hands back Result, How it was calculated and Reverse conversion. Values update as you type, so comparing options is a matter of editing one field.

Typical users are students converting units for homework. Unit mistakes are quietly expensive. They have wrecked spacecraft and ruined recipes alike.

Because it is all local, the tool is as fast as your device and as private as your own notes.

Below the tool you will find the field reference, the method, and an example computed from the values it opens with.

What do the Equivalent Dose Converter fields mean?

The Equivalent Dose Converter uses 3 inputs. Sensible defaults are loaded up front, which means you can change one number at a time instead of filling the whole form first.

How does the Equivalent Dose Converter work?

Both units are converted through equivalent dose's base unit (Sv), so any of the 5 units in the dropdowns can be paired in either direction without loss of accuracy.

Exact definitions are preferred throughout: the metre, the inch and the pound all have them. Only where a unit depends on a measured constant is an accepted published value substituted.

Worked example

These are the values the Equivalent Dose Converter loads by default, and the result it produces from them. These are the exact values loaded when the page opens, and the answer they produce.

Equivalent radiation dose

1 sievert (Sv) equals exactly 100 rem, the older unit, but critically, equivalent dose is not the same physical quantity as absorbed dose (gray/rad): it weights the absorbed energy by a factor reflecting how biologically damaging that specific type of radiation is, so gray and sievert are not simply interchangeable.

Worth knowing

• For X-rays, gamma rays and beta particles, the weighting factor is 1, so the numeric value in gray and sievert happens to be the same for those radiation types, but for alpha particles, the weighting factor is 20, meaning 1 gray of alpha radiation delivers an equivalent dose of 20 sievert, a genuinely important distinction in radiation safety that a naive "Gy equals Sv" assumption would get badly wrong.
• Typical background radiation exposure for a person is roughly 2 to 3 millisieverts per year from natural sources (cosmic rays, radon, and naturally occurring radioactive materials in soil and rock), a useful reference point for interpreting medical or occupational dose figures.
• The rem, like the rad it pairs with, still appears in some older US regulatory and medical documentation, converting to sievert at the same clean factor of 100 used for the gray/rad relationship.

Definitions: BIPM SI Brochure · NIST reference on units

How to use it

1. Type Value.
2. Pick a value for From: the options are Sievert (Sv), Millisievert (mSv), Microsievert (µSv), Rem (rem) or Millirem (mrem).
3. Pick a value for To: the options are Sievert (Sv), Millisievert (mSv), Microsievert (µSv), Rem (rem) or Millirem (mrem).
4. The results panel stays in sync with the form as you edit it.
5. Look at Result, How it was calculated and Reverse conversion in the output panel.
6. Print gives a tidy version without the navigation, which is handy for attaching to a file.

What this tool does not do

• Factors use the internationally agreed definitions; some industries round them differently.
• Repeated conversions compound rounding, so convert once from the original value where you can.
• Comparisons across tools can differ where each uses a slightly different definition.
• Nothing here can catch a correct number entered in the wrong field.

Frequently asked questions

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