The Double-Struck Capital C symbol (ℂ). Copy and paste it, or use its Unicode, HTML, and CSS codes.
More from Letterlike Symbols.
The quickest way is to copy ℂ from this page and paste it anywhere. You can also insert it with its Unicode, HTML, or alt code listed above.
ℂ is U+2102 (decimal 8450).
Use ℂ in HTML to render ℂ on a web page.
On Windows you can type it with Alt+8450 (hold Alt and enter the number on the numeric keypad).
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