Radiation Dose Converter Free Online
Convert radiation dose equivalent and absorbed dose. Sv (effective dose) and Gy (absorbed dose) share the unit J/kg but differ by radiation weighting factor (=1 for X-ray, gamma, beta).
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Radiation Dose Converter Features
Medical & Nuclear
Background radiation ~3 mSv/year. Chest X-ray ~0.1 mSv. CT scan 5–15 mSv. Mammogram ~0.4 mSv. Annual occupational limit (US) 50 mSv.
SI & Legacy
Sievert (SI) and rem (legacy US): 1 Sv = 100 rem. Gray (SI) and rad: 1 Gy = 100 rad. Sv/rem are biologically weighted; Gy/rad are physical absorbed dose.
Effective vs Absorbed
For X-ray, gamma, beta: Sv = Gy numerically (weighting factor = 1). For alpha and neutrons, Sv = Gy × wR (wR = 5–20). This tool treats them identically — multiply for alpha/neutron.
Live Conversion
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Swap Units
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Free vs Pro
| Feature | Free | Pro |
|---|---|---|
| Full radiation dose conversion | ||
| Live conversion | ||
| All-units result panel | ||
| Bulk CSV / Excel conversion | — | |
| REST API access | — | |
| Custom precision settings | — |
Frequently Asked Questions
1 mSv = 100 mrem. So 5 mSv = 500 mrem. Conversely, 1 mrem = 0.01 mSv = 10 μSv. The US still uses rem; rest of the world uses Sv.
About 3 mSv/year (300 mrem) globally average — half from radon gas, the rest from cosmic rays, soil radioisotopes, and food. Higher in places like Denver (4–5 mSv/y).
Numerically yes for X-ray, gamma, beta (weighting factor = 1). For alpha radiation Sv = Gy × 20; for fast neutrons Sv = Gy × 10. The Sv accounts for biological damage; Gy is pure energy deposited.
Chest CT ~7 mSv. Abdominal/pelvic CT 8–15 mSv. Whole-body PET-CT ~25 mSv. Compare to chest X-ray ~0.1 mSv (single image) and dental panoramic ~0.025 mSv.
Acute radiation syndrome onset ~1 Sv (100 rem) whole-body. 50% lethal at ~4–5 Sv without treatment. Annual occupational limit is 50 mSv (US) or 20 mSv (most other countries).