# Radiation Dose Converter (Gy, Sv, rad, rem)

URL: https://speedycalculator.com/calculators/conversion/radiation-converter/
Last updated: 2026-10-25

> The radiation converter switches absorbed dose between grays, milligrays and rads, and turns it into equivalent dose in sieverts, millisieverts and rem using the radiation weighting factor for the type of radiation.

## Inputs

- Absorbed dose (mGy, Gy, µGy, rad, krad)
- Type of radiation

## Results

- Absorbed dose
- In rad
- Equivalent dose
- In rem
- In microsieverts

## Formula

```
H (Sv) = D (Gy) × w_R
1 rad = 0.01 Gy;  1 rem = 0.01 Sv
```

## Explanation

Absorbed dose (gray) measures energy deposited per kilogram of tissue. Equivalent dose (sievert) multiplies it by a weighting factor because alpha particles and neutrons do more biological damage than X-rays for the same energy. For X-rays, gamma rays and beta particles the factor is 1, so 1 Gy gives 1 Sv.

### How to use the Radiation Dose Converter

- **Absorbed dose**
- **Type of radiation**
- Every result field is editable: type into **Absorbed dose** or any other result and **Absorbed dose** plus every other field update to match.

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Your dose is converted to grays, then multiplied by the ICRP radiation weighting factor to give the equivalent dose in sieverts and its sub-units.

### Typical doses for comparison

ExposureApproximate doseDental X-ray0.005 mSvLong-haul flight (10 h)0.03–0.05 mSvChest X-ray0.02–0.1 mSvMammogram0.4 mSvHead CT scan2 mSvAnnual natural background (world average)2.4 mSvAnnual limit for radiation workers (ICRP)20 mSv averaged over 5 years

### Good to know

Effective dose (also in sieverts) adds tissue weighting factors on top of the radiation weighting factor to estimate whole-body risk. This converter handles units and radiation type only; it is not a substitute for a medical physicist’s dose assessment.

### Inputs explained

FieldWhat to enterAbsorbed doseUnits: mGy, Gy, µGy, rad, kradType of radiationChoose one: X-rays, gamma rays, beta (w_R = 1), Protons (w_R = 2), Neutrons, typical (w_R ≈ 10), Alpha particles, heavy ions (w_R = 20)

### What each result means

- **Equivalent dose** = [Absorbed dose] × [Type of radiation]
- **In rem** = [Absorbed dose] × [Type of radiation]
- **In microsieverts** = [Absorbed dose] × [Type of radiation]

## Worked example

Inputs — Absorbed dose: 1 mGy; Type of radiation: X-rays, gamma rays, beta (w_R = 1).

Results — Absorbed dose = 0.001 Gy; In rad = 0.1 rad; **Equivalent dose = 1 mSv**; In rem = 0.1 rem; In microsieverts = 1,000 µSv.

## Key terms

- **Gray (Gy)**: SI unit of absorbed dose: 1 joule of radiation energy per kilogram.
- **Sievert (Sv)**: SI unit of equivalent and effective dose, adjusting for radiation type and tissue.

## FAQ

**How much radiation is a chest X-ray?**
About 0.02–0.1 mSv effective dose.

**What is the average yearly background dose?**
About 2.4 mSv worldwide (around 3 mSv in the U.S.).

**Is a sievert the same as a gray?**
Only when the weighting factor is 1 (X-rays, gamma, beta).

**What formula does the Radiation Dose Converter use?**
H (Sv) = D (Gy) × w_R.


## Sources

- [ICRP Publication 103 – The 2007 Recommendations of the International Commission on Radiological Protection](https://www.icrp.org/publication.asp?id=ICRP%20Publication%20103)
- [NIST Special Publication 811 – Guide for the Use of the International System of Units](https://www.nist.gov/pml/special-publication-811)
- [NIST Handbook 44 Appendix C – General tables of units of measurement](https://www.nist.gov/pml/owm/nist-handbook-44-current-edition)