processconvert
Radioactivity

CitomCi

Convert curies (Ci) to millicuries (mCi).

Factor1 Ci = 1000 mCi

Converter

Ci

Accepts numbers or expressions, e.g. 150 + 14.7

Result
1000mCi

Rendered to 6 significant figures.

Formula

Formula
mCi = Ci × 1000

Multiply any value in curies by 1000 to obtain the value in millicuries.

Worked example

Convert 1 Ci to mCi.

  1. 01Start with 1 Ci.
  2. 02Multiply by the conversion factor: 1 × 1000 = 1000 mCi.
Result1 Ci = 1000 mCi

Conversion table

CimCi
11000
22000
55000
1010000
2020000
5050000
1001.0000e+5
2002.0000e+5
5005.0000e+5
10001.0000e+6

Reference values rounded to 5 significant figures for display.

FAQ

What is the conversion factor from Ci to mCi?
1 Ci equals 1000 mCi. To convert, multiply the value in curies by 1000.
How do I convert 1 Ci to mCi?
1 Ci = 1000 mCi. For any value, multiply by 1000.
How do I convert mCi back to Ci?
Divide by the same factor — or equivalently, multiply by 0.001. So 1 mCi = 0.001 Ci.
When would I need to convert curie to millicurie?
Radioactivity (activity) conversions between Ci and mCi are routine in health physics, nuclear medicine ordering, environmental monitoring, radiopharmacy and reactor/accelerator-source documentation. The becquerel (Bq) is the SI unit; the curie (Ci) is the legacy unit (1 Ci ≡ 3.7×10¹⁰ Bq exactly). This category is strictly activity (decays per second) — it does NOT cover absorbed dose (Gy, rad), dose equivalent (Sv, rem), exposure or dose rate, all of which are different physical quantities and live in separate categories.
Is the conversion exact?
The factor shown is precise to at least 7 significant figures. For most process-engineering work this is far better than instrument accuracy. For metrology or trade applications, refer to the relevant national standard (NIST, BIPM, ISO 80000).

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