Convert Curies to Millicuries (Ci to mCi)
1 curie (Ci) = 1000 millicuries (mCi). 1 mCi = 0.001 Ci. Example: 15 Ci = 15 × 1000 = 15000 mCi.
Also searched as curies to mCi, curies in mCi, curies into millicuries, Ci to mCi, Ci in millicuries, Ci into millicurie, curie to millicurie, Ci to millicuries converter and how many millicuries in a curie.
1 Ci = 1000 mCi
Type in either box. Scientific notation works: 1.5e-3.
Converting a list? Use the bulk curie to millicurie converter to paste a column from Excel.
How to Convert Curie to Millicurie
- 1 Ci = 1000 mCi
- 1 mCi = 0.001 Ci
- Example: convert 15 Ci to mCi: 15 Ci = 15 × 1000 mCi = 15000 mCi
Formula
mCi = Ci × 1000
Derivation from SI units:
- 1 Ci = 3.7 × 10¹⁰ Bq exactly (originally the activity of 1 g of radium-226).
- 1 mCi = 3.7 × 10⁷ Bq = 37 MBq.
- 1 Ci = 37000000000 Bq ÷ 37000000 Bq per mCi = 1000 mCi
Both units are defined exactly, so the factor is exact. Curie definition: curie; Millicurie definition: millicurie.
Worked examples
- A reading of 2 Ci converts to 2000 mCi.
2 Ci × 1000 = 2000 mCi - A value of 20 Ci is 20000 mCi.
20 Ci × 1000 = 20000 mCi
Curie to Millicurie conversion table
| Curies (Ci) | Millicuries (mCi) |
|---|---|
| 0.1 Ci | 100 mCi |
| 0.5 Ci | 500 mCi |
| 1 Ci | 1000 mCi |
| 2 Ci | 2000 mCi |
| 5 Ci | 5000 mCi |
| 10 Ci | 10000 mCi |
| 20 Ci | 20000 mCi |
| 50 Ci | 50000 mCi |
| 100 Ci | 100000 mCi |
| 1000 Ci | 1000000 mCi |
Where it's used
Curies are used for US nuclear regulation and licences, while millicuries appear in US radiopharmaceutical doses (e.g. 10 mCi FDG). Both measure activity of a radioactive source, so the conversion is a fixed factor.
Curie to other radioactivity units
| Conversion | 1 Ci equals |
|---|---|
| curie to millicurie | 1000 mCi |
| curie to becquerel | 37000000000 Bq |
| curie to megabecquerel | 37000 MBq |
| curie to picocurie | 1000000000000 pCi |
| curie to kilobecquerel | 37000000 kBq |
| curie to gigabecquerel | 37 GBq |
| curie to microcurie | 1000000 µCi |
| curie to disintegration per minute | 2220000000000 dpm |
Show 3 more units
| curie to terabecquerel | 0.037 TBq |
|---|---|
| curie to nanocurie | 1000000000 nCi |
| curie to rutherford | 37000 Rd |
Frequently asked questions
How many millicuries are in 1 curie?
1 Ci = 1000 mCi.
How do I convert curies to millicuries?
Multiply the value in Ci by 1000. For example, 15 Ci × 1000 = 15000 mCi.
Is the Ci to mCi conversion exact?
Yes. Both units are defined exactly, and 1 Ci is exactly 1000 mCi.
Sources
- Guide for the Use of the International System of Units (SI), NIST Special Publication 811, 2008 Edition, National Institute of Standards and Technology , Appendix B.8, "curie".
Last reviewed: . Factors are stored exactly and computed with 50-digit decimal arithmetic. See how we verify conversion factors.
Cite this page
APA
Scientific Converters. (2026, October 15). Convert Curies to Millicuries (Ci to mCi). Retrieved October 25, 2026, from https://scientificconverters.com/radioactivity/curies-to-millicuries/
IEEE
Scientific Converters, "Convert Curies to Millicuries (Ci to mCi)," scientificconverters.com. Accessed: Oct. 25, 2026. [Online]. Available: https://scientificconverters.com/radioactivity/curies-to-millicuries/