Becquerels to curies

Type a value in becquerels to see it in curies straight away, or type in the second box to convert back.

Loading the tool…

Processing and privacy: The result is calculated inside your browser and your data is not sent to any server.

How to use it

  1. Type the value in the becquerels box.
  2. Read the result in curies as you type, and pick the precision you need.
  3. Swap the direction to convert back, or copy the result.

How it is calculated

Ci = Bq × 2.702702703e-11

Multiply the value in becquerels by 2.702702703e-11 to get curies.

Example

To convert 25 Bq to curies: 25 × 2.702702703e-11 = 6.75676e-10 Ci.

Conversion table

Becquerels (Bq)Curies (Ci)
12.7027e-11
25.40541e-11
38.10811e-11
51.35135e-10
102.7027e-10
205.40541e-10
256.75676e-10
501.35135e-9
1002.7027e-9
2506.75676e-9
5001.35135e-8
1,0002.7027e-8

About the units

Becquerel
The SI unit of radioactivity, equal to one nuclear decay per second.
Curie
An older unit of radioactivity equal to exactly 3.7 × 10^10 becquerels, originally close to the activity of one gram of radium-226.

Limits and caveats

  • Results are rounded for display and computed with the browser's floating point precision (about 15 significant digits).
  • Both unit factors are exact by their official definitions.

Questions about this tool

How many curies are in one becquerel?

1 Bq = 2.7027e-11 Ci exactly.

How do I convert becquerels to curies?

Use Ci = Bq × 2.702702703e-11. For example, 25 Bq = 6.75676e-10 Ci.

How many becquerels are in one curie?

1 Ci = 37,000,000,000 Bq.

Why is a curie 3.7 × 10^10 becquerels?

The curie was first based on the activity of one gram of radium-226, then fixed at exactly 3.7 × 10^10 decays per second.

Is a becquerel the same as a hertz?

Both equal one per second, but the SI reserves the becquerel for radioactive decay and the hertz for periodic phenomena.